Config Template doesn't respect variable names sections

More information here:

https://github.com/ceph/ceph-ansible/issues/3496

Config Template will create duplicate sections if the override contains a section header that is a variable name. For example, using the following playbook and template file:

# cat playbooks/templates/test.file.j2
#This is my test file

[{{ ansible_hostname }}]
a = 1
b = 2
c = 3

# cat playbooks/test.yml
---
- name: test playbook
  hosts: localhost
  connection: local
  gather_facts: true
  tasks:
    - config_template:
        src: "templates/test.file.j2"
        config_type: "ini"
        config_overrides: "{{ my_overrides }}"
        dest: "/opt/test.file"
  vars:
    my_overrides:
      "{{ ansible_hostname }}":
        d: 4
        e: 5
        a: 3

# cat /opt/test.file
#This is my test file
[ubuntu]
a = 1
b = 2
c = 3

[ubuntu]
a = 3
d = 4
e = 5