Implement group level MR approval rules
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* Ensure the frontend has the necessary data on the Group level (Group > Settings).
* UI changes: render the component created in step 3 (behind feature flag) and ensure backend receives the correct data.
* Backend/frontend integration on the Group level.
See [this comment](https://gitlab.com/groups/gitlab-org/-/epics/11451#note_1559373884) for additional context.
# Frontend work
1. Conditionally allow for dropdown, when for group level (can be implemented when working on group level)
1. Conditionally render `unconfigured_security_rules.vue`, when for project level (can be implemented when working on group level).
1. Conditionally render table footer, when for group level (can be implemented when working on group level).
1. Integration with backend
In https://gitlab.com/gitlab-org/gitlab/-/issues/425184 we'll add a lock as shown in https://gitlab.com/gitlab-org/gitlab/-/issues/425433/designs/project_with_inherited_group_level_mr_approval_rules.png
### Availability and Testing
Additional feature specs:
- Ensure group level approval rule can be inherited by a project
- Ensure that if group level approval rules are present, project level approval rules cannot be created
- Ensure MR's created within a group with group approval rules, get those approval rules
(Some of these specs may be created with https://gitlab.com/gitlab-org/gitlab/-/issues/425184)
Regression testing, please ensure associated MR is labelled with ~"pipeline:run-all-e2e" and `e2e:package-and-test` job is passing.
issue