/projects/:id/approvals cannot set multiple options from UI
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### Summary
GitLab web UI has options in 'Settings / General / Merge request approvals' called `Require approval from code owners` and `Prevent approval of merge requests by merge request committers`. These options have no equivalent in the Merge request approvals API (https://docs.gitlab.com/ee/api/merge_request_approvals.html).
### Steps to reproduce
1. Perform an HTTP GET to /projects/:id/approvals.
2. Observe there are no fields for `Require approval from code owners` and `Prevent approval of merge requests by merge request committers`.
3. Check the boxes in the GitLab web UI.
4. Click 'Save changes'.
5. Perform an HTTP GET to /projects/:id/approvals.
6. Observe no change in output compared to step 2.
1. Browse to documentation at https://docs.gitlab.com/ee/api/merge_request_approvals.html.
2. Observe there is no documentation for the fields `Require approval from code owners` and `Prevent approval of merge requests by merge request committers`.
### Example Project
Project is irrelevant. This is not project specific.
### What is the current *bug* behavior?
`Require approval from code owners` and `Prevent approval of merge requests by merge request committers` cannot be retrieved or set using the Merge request approvals API and must be manually set in the GitLab web UI.
### What is the expected *correct* behavior?
`Require approval from code owners` and `Prevent approval of merge requests by merge request committers` can be set using the Merge request approvals API.
### Relevant logs and/or screenshots
```
# http --check-status "GET" "https://<host>/api/v4/projects/<id>/approvals" Private-Token:"<token>" | jq
{
"approvers": [],
"approver_groups": [],
"approvals_before_merge": 1,
"reset_approvals_on_push": true,
"disable_overriding_approvers_per_merge_request": true,
"merge_requests_author_approval": false
}
```
### Output of checks
n/a
#### Results of GitLab environment info
do not have access
version is GitLab Enterprise Edition 11.11.2-ee
#### Results of GitLab application Check
n/a
### Possible fixes
https://gitlab.com/gitlab-org/gitlab-ee/blob/a0228bb80d3ccaa9b5606a37b53e7dad7d7863d0/ee/lib/api/project_approvals.rb#L28-32
appears to be missing `merge_requests_require_code_owner_approval` and `merge_requests_disable_committers_approval`.
issue