---
- import_tasks: setup_no_value.yml

- name: unsetting value
  git_config:
    name: "{{ option_name }}"
    scope: "{{ option_scope }}"
    state: absent
  register: unset_result

- name: getting value
  git_config:
    name: "{{ option_name }}"
    scope: "{{ option_scope }}"
  register: get_result

- name: assert unsetting didn't change
  assert:
    that:
      - unset_result.changed == false
      - unset_result.msg == 'no setting to unset'
      - get_result.config_value == ''
...