Request edit commit message be displayed by default on MRs with push rules
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### Summary
When merging a branch, if the MR title does not match to the push rules configured, an error will be thrown. This is expected behavior if you do not edit the commit message before clicking Merge. Requesting that the checkbox be checked by default and as an added bonus, the push rules are shown as a reference.
### Steps to reproduce
1. Configure push rules in **Settings** -> **Repository** -> **Push rules** -> **Require expression in commit messages** (ex: `(add|remove).*`)
2. Create new merge request and set title to _not_ match the push rules
3. Attempting to merge throws an error
### Example Project
https://gitlab.com/mbadeau/zd-393540
### What is the current *bug* behavior?
If the MR title does not match the push rules, it will fail to merge.
### What is the expected *correct* behavior?
MR title should not affect push rules and should only take on the name of the current branch and not the MR branch name
### Relevant logs and/or screenshots

(sorry for tiny video)
### Output of checks
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This bug happens on GitLab.com
### Possible fixes
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issue