[QUARANTINE] [nightly] Create with merge request suggestions applies a single suggestion with a custom message

What does this MR do?

Quarantines the test Create with merge request suggestions applies a single suggestion with a custom message (https://gitlab.com/gitlab-org/gitlab/-/blob/master/qa/qa/specs/features/browser_ui/3_create/merge_request/suggestions/custom_commit_suggestion_spec.rb#L44)

This test has been found by Confiner to have failed 14 times, which exceeds the threshold of 3 times.

1. ee:update
2. ce:upgrade
3. ee:instance-image
4. ee:instance-image-slow-network
5. ee:nplus1-instance-image
6. ee:instance-image
7. ee:instance-image-slow-network
8. ee:nplus1-instance-image
9. ee:update
10. ee:instance-image
11. ee:instance-image-slow-network
12. ee:nplus1-instance-image
13. ce:upgrade
14. ee:instance-image

#377680 (closed)

(This MR was automatically generated by Confiner at 2023-03-20 01:18:01 UTC)