Backport Required Merge Request Approvals from Starter to CE
## Problem to solve
[Merge Request Approvals](https://docs.gitlab.com/ee/user/project/merge_requests/merge_request_approvals.html#merge-request-approvals-starter) are implemented in Starter/Bronze (Gitlab EE), but are not available in Core (Gitlab CE).
Even the smallest development teams (2-3 people) and personal/non-commercial projects require essential features for good coding practices like peer-reviewing:
* Selection of reviewers from a list
* Blocking of merge requests until all reviewers approve them
## Further details: abstract of the discussion bellow
Gitlab is not currently, [as of 2019-06-07](https://gitlab.com/gitlab-org/gitlab-ce/issues/42096#note_179043320), willing to move the [Merge Request Approvals](https://docs.gitlab.com/ee/user/project/merge_requests/merge_request_approvals.html#merge-request-approvals-starter) feature from Starter to CE.
There is a separate issue (https://gitlab.com/gitlab-org/gitlab-ce/issues/59197) for which Gitlab is accepting merge requests though. Gitlab will allow contributors to propose merge-requests based on EE code for the features described in that issue.
https://gitlab.com/gitlab-org/gitlab-ce/issues/59197 proposes:
* Add the **Approve** button to the merge request widget as an entirely optional step
* Number of approvals and a green tick would be shown in the merge request list
Which improves the current situation in this way:
* It is better than relying on norms/culture, like using :heavy_check_mark: or :white_check_mark: reaction to note approval in a merge request
* Number of approvals (and a green tick) shown in the MR list
It does not allow (and merge-requests implementing this will probably be rejected):
* Selection of reviewers from a list
* Blocking of merge requests until all reviewers approve them
## Proposal
GitLab should make the [Merge Request Approvals](https://docs.gitlab.com/ee/user/project/merge_requests/merge_request_approvals.html#merge-request-approvals-starter) feature available in Core (GitLab CE).
issue