Require build before allowing merge (not just lack of failed build)

Description

My organization would like to require that an open MR has built successfully before merging. The currently implemented feature

http://gitlab.lgc.com/help/user/project/merge_requests/merge_when_build_succeeds#only-allow-merge-requests-to-be-merged-if-the-build-succeeds

Prevents merge if the latest build failed, but not if there have been no builds attempted (see images below). This allows a window between the MR being opened and the first CI build of the MR starting, where it can be merged with no build status.

Proposal

Replace the current Only allow merge requests to be merge if the build succeeds with a combobox of 3 choices:

1. No build requirement
2. No failed builds
3. Must have successful build

Links / references

Merge Request requires successful build

Open MR can be merged with no builds posted