Follow-up from "Comparison page: GH Pull Request vs GL Merge Request"

The following discussions from !5979 (merged) should be addressed:

• @axil started a discussion:

  @marcia I had removed this file in a previous commit, we don't use it anymore. Can you delete it please? ♥

• @axil started a discussion:

  @marcia this is now supported by GitHub as well! https://github.com/blog/2293-resolve-simple-merge-conflicts-on-github

• @axil started a discussion:

  This is also true for GitHub https://help.github.com/articles/closing-issues-via-commit-messages/

• @axil started a discussion:

  Only available when the review app is deployed on Kubernetes, we should stress that out!

• @axil started a discussion:

  Not sure what you want to say here with shell executor 🤔 This is also true for all others executors.

• @axil started a discussion:

  Not sure how relevant this is with the MR/PR and the comparison we're doing here. This is a CI feature ;)