Manila ceph configuration won't work in HA mode

**Bug Report**

What happened:

When more than one manila_share instance is setup with external ceph, problems occur as in the current kolla-ansible configuration the containers share the same auth ID. (With each restart of the manila_share container on a controller the ceph sessions for the other controllers are evicted).

In the manila-share logs:
In the below chunk of logs you can see each instance of manila seems to run a chunk of code to evict all other clients named manila... happens at 14:49:16.939 (06-37), 14:49:17.031 (06-39), and 14:49:17.022 (06-41).
$ ansible -i /etc/kolla/multinode control -m shell -a "grep -iR '2020-11-24 14:49:' /var/log/kolla/manila/manila-share.log"
B-06-37-openstack-ctl.maas | CHANGED | rc=0 >>
2020-11-24 14:49:16.459 6 INFO oslo_service.periodic_task [-] Skipping periodic task update_share_usage_size because it is disabled
2020-11-24 14:49:16.475 6 INFO oslo_service.service [req-f32e40b4-3566-49d6-957f-6fb480c42db6 - - - - -] Starting 1 workers
2020-11-24 14:49:16.483 19 INFO manila.service [-] Starting manila-share node (version 10.0.2)
2020-11-24 14:49:16.918 19 INFO manila.share.drivers.cephfs.driver [req-71c01790-6d75-4cf6-97f8-904d795727fe - - - - -] [CEPHFS1}] Ceph client found, connecting...
2020-11-24 14:49:16.939 19 INFO ceph_volume_client [req-71c01790-6d75-4cf6-97f8-904d795727fe - - - - -] evict clients with auth_name=manila
2020-11-24 14:49:16.944 19 INFO ceph_volume_client [req-71c01790-6d75-4cf6-97f8-904d795727fe - - - - -] evict: joined all
2020-11-24 14:49:16.949 19 INFO manila.share.drivers.cephfs.driver [req-71c01790-6d75-4cf6-97f8-904d795727fe - - - - -] [CEPHFS1] Ceph client connection complete.
2020-11-24 14:49:16.962 19 INFO manila.share.manager [req-71c01790-6d75-4cf6-97f8-904d795727fe - - - - -] Updating share status
2020-11-24 14:49:16.977 19 INFO manila.share.manager [req-71c01790-6d75-4cf6-97f8-904d795727fe - - - - -] Finished initialization of driver: 'CephFSDriver@B-06-37-openstack-ctl@cephfsnative1'
B-06-39-openstack-ctl.maas | CHANGED | rc=0 >>
2020-11-24 14:49:16.584 6 INFO oslo_service.periodic_task [-] Skipping periodic task update_share_usage_size because it is disabled
2020-11-24 14:49:16.599 6 INFO oslo_service.service [req-498d5964-a9e3-4484-8a7e-f2d894fc4e9f - - - - -] Starting 1 workers
2020-11-24 14:49:16.606 19 INFO manila.service [-] Starting manila-share node (version 10.0.2)
2020-11-24 14:49:17.012 19 INFO manila.share.drivers.cephfs.driver [req-10e0d7ef-bf38-4352-95ea-80edab67e0bb - - - - -] [CEPHFS1}] Ceph client found, connecting...
2020-11-24 14:49:17.031 19 INFO ceph_volume_client [req-10e0d7ef-bf38-4352-95ea-80edab67e0bb - - - - -] evict clients with auth_name=manila
2020-11-24 14:49:17.590 19 INFO ceph_volume_client [req-10e0d7ef-bf38-4352-95ea-80edab67e0bb - - - - -] evict: joined all
2020-11-24 14:49:17.595 19 INFO manila.share.drivers.cephfs.driver [req-10e0d7ef-bf38-4352-95ea-80edab67e0bb - - - - -] [CEPHFS1] Ceph client connection complete.
2020-11-24 14:49:17.615 19 INFO manila.share.manager [req-10e0d7ef-bf38-4352-95ea-80edab67e0bb - - - - -] Updating share status
2020-11-24 14:49:17.633 19 INFO manila.share.manager [req-10e0d7ef-bf38-4352-95ea-80edab67e0bb - - - - -] Finished initialization of driver: 'CephFSDriver@B-06-39-openstack-ctl@cephfsnative1'
B-06-41-openstack-ctl.maas | CHANGED | rc=0 >>
2020-11-24 14:49:16.569 7 INFO oslo_service.periodic_task [-] Skipping periodic task update_share_usage_size because it is disabled
2020-11-24 14:49:16.585 7 INFO oslo_service.service [req-79fa62e5-dcff-4c19-a516-143844096da7 - - - - -] Starting 1 workers
2020-11-24 14:49:16.591 20 INFO manila.service [-] Starting manila-share node (version 10.0.2)
2020-11-24 14:49:17.000 20 INFO manila.share.drivers.cephfs.driver [req-d9be838e-8a1e-4b14-b43b-979d97a7e5dd - - - - -] [CEPHFS1}] Ceph client found, connecting...
2020-11-24 14:49:17.022 20 INFO ceph_volume_client [req-d9be838e-8a1e-4b14-b43b-979d97a7e5dd - - - - -] evict clients with auth_name=manila
2020-11-24 14:49:17.589 20 INFO ceph_volume_client [req-d9be838e-8a1e-4b14-b43b-979d97a7e5dd - - - - -] evict: joined all
2020-11-24 14:49:17.594 20 INFO manila.share.drivers.cephfs.driver [req-d9be838e-8a1e-4b14-b43b-979d97a7e5dd - - - - -] [CEPHFS1] Ceph client connection complete.
2020-11-24 14:49:17.613 20 INFO manila.share.manager [req-d9be838e-8a1e-4b14-b43b-979d97a7e5dd - - - - -] Updating share status
2020-11-24 14:49:17.633 20 INFO manila.share.manager [req-d9be838e-8a1e-4b14-b43b-979d97a7e5dd - - - - -] Finished initialization of driver: 'CephFSDriver@B-06-41-openstack-ctl@cephfsnative1'

That maps to https://github.com/openstack/manila/blob/stable/ussuri/manila/share/drivers/cephfs/driver.py#L220 - specifically this chunk of code when a volume client is created:
```
        self._volume_client = ceph_volume_client.CephFSVolumeClient(
            auth_id, conf_path, cluster_name, volume_prefix=volume_prefix)
        LOG.info("[%(be)s}] Ceph client found, connecting...",
                 {"be": self.backend_name})
        if auth_id != CEPH_DEFAULT_AUTH_ID:
            # Evict any other manila sessions. Only do this if we're
            # using a client ID that isn't the default admin ID, to avoid
            # rudely disrupting anyone else.
            premount_evict = auth_id
        else:
            premount_evict = None
        try:
            self._volume_client.connect(premount_evict=premount_evict)
```
that calls https://github.com/ceph/ceph/blob/octopus/src/pybind/ceph_volume_client.py#L488 ... which specifically notes: ```
        :param premount_evict: Optional auth_id to evict before mounting the filesystem: callers
                               may want to use this to specify their own auth ID if they expect
                               to be a unique instance and don't want to wait for caps to time
                               out after failure of another instance of themselves.```

https://documentation.suse.com/external-tree/en-us/soc/9/openstack/user/html/manila/admin/cephfs_driver.html also mentions:
```A CephFS driver instance, represented as a backend driver section in manila.conf, requires a Ceph auth ID unique to the backend Ceph Filesystem. Using a non-unique Ceph auth ID will result in the driver unintentionally evicting other CephFS clients using the same Ceph auth ID to connect to the backend.```

The kolla-ansible configuration for Manila uses the same auth id for all the manila-share instances rather than the unique IDs which seem to be required, thus resulting in this pattern of evictions.

Manually setting each of the manila instances to use a separate auth id seems to result in multiple manila-share containers functioning without interfering with each other. (Updating the config.json to stage in a different key for each controller and then updating the manila.conf to reference this separate auth id).

(Note that we don't have `enable_manila_backend_cephfs_nfs` enabled. It's unclear as to whether or not this would necessitate a separate keyring for each of those as well - i.e. from 1 auth id per controller to 2 per controller).

What you expected to happen:

Multiple `manila_share` containers function without interfering with each other.

How to reproduce it (minimal and precise):

Deploy manila with external ceph and manila enabled.

```
enable_manila: "yes"
enable_manila_backend_cephfs_native: "yes"
```

**Environment**:
* OS (e.g. from /etc/os-release):
* Kernel (e.g. `uname -a`): Linux B-06-39-openstack-ctl 5.4.0-54-generic #60~18.04.1-Ubuntu SMP Fri Nov 6 17:25:16 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux
* Docker version if applicable (e.g. `docker version`): 19.03.13
* Kolla-Ansible version (e.g. `git head or tag or stable branch` or pip package version if using release): stable/ussuri
* Docker image Install type (source/binary): source
* Docker image distribution:
* Are you using official images from Docker Hub or self built? self-built
* If self built - Kolla version and environment used to build: stable/ussuri
* Share your inventory file, globals.yml and other configuration files if relevant