Missing vip config shouldn't be a critical error - AttributeError: 'NoneType' object has no attribute 'split'

Deploying the charm from jammy/stable and relate it with ceph-mon leads to an error status immediately.

ceph-loadbalancer error 1 openstack-loadbalancer jammy/stable 10 no hook failed: "loadbalancer-relation-changed"

The error is about missing vip a vip config, but it shouldn't be a critical error. Instead, the status can be "blocked".

unit-ceph-loadbalancer-0: 12:29:54 ERROR unit.ceph-loadbalancer/0.juju-log loadbalancer:10: Uncaught exception while in charm code:
Traceback (most recent call last):
  File "/var/lib/juju/agents/unit-ceph-loadbalancer-0/charm/./src/charm.py", line 153, in <module>
    main(OpenstackLoadbalancerCharm)
  File "/var/lib/juju/agents/unit-ceph-loadbalancer-0/charm/venv/ops/main.py", line 431, in main
    _emit_charm_event(charm, dispatcher.event_name)
  File "/var/lib/juju/agents/unit-ceph-loadbalancer-0/charm/venv/ops/main.py", line 142, in _emit_charm_event
    event_to_emit.emit(*args, **kwargs)
  File "/var/lib/juju/agents/unit-ceph-loadbalancer-0/charm/venv/ops/framework.py", line 283, in emit
    framework._emit(event)
  File "/var/lib/juju/agents/unit-ceph-loadbalancer-0/charm/venv/ops/framework.py", line 743, in _emit
    self._reemit(event_path)
  File "/var/lib/juju/agents/unit-ceph-loadbalancer-0/charm/venv/ops/framework.py", line 790, in _reemit
    custom_handler(event)
  File "/var/lib/juju/agents/unit-ceph-loadbalancer-0/charm/venv/interface_openstack_loadbalancer/loadbalancer.py", line 213, in _on_relation_changed
    self.on.lb_requested.emit()
  File "/var/lib/juju/agents/unit-ceph-loadbalancer-0/charm/venv/ops/framework.py", line 283, in emit
    framework._emit(event)
  File "/var/lib/juju/agents/unit-ceph-loadbalancer-0/charm/venv/ops/framework.py", line 743, in _emit
    self._reemit(event_path)
  File "/var/lib/juju/agents/unit-ceph-loadbalancer-0/charm/venv/ops/framework.py", line 790, in _reemit
    custom_handler(event)
  File "/var/lib/juju/agents/unit-ceph-loadbalancer-0/charm/./src/charm.py", line 150, in _process_lb_requests
    self._send_loadbalancer_response()
  File "/var/lib/juju/agents/unit-ceph-loadbalancer-0/charm/./src/charm.py", line 115, in _send_loadbalancer_response
    for binding, vips in self._get_space_vip_mapping().items():
  File "/var/lib/juju/agents/unit-ceph-loadbalancer-0/charm/./src/charm.py", line 105, in _get_space_vip_mapping
    bindings[binding_name] = [
  File "/var/lib/juju/agents/unit-ceph-loadbalancer-0/charm/./src/charm.py", line 108, in <listcomp>
    for vip in self.vips
  File "/var/lib/juju/agents/unit-ceph-loadbalancer-0/charm/./src/charm.py", line 100, in vips
    return self.config.get('vip').split()
AttributeError: 'NoneType' object has no attribute 'split'
unit-ceph-loadbalancer-0: 12:29:55 ERROR juju.worker.uniter.operation hook "loadbalancer-relation-changed" (via hook dispatching script: dispatch) failed: exit status 1