Merge branch...

Merge branch '18446-when-this-merge-request-is-accepted-this-issue-will-be-closed-automatically-rendered-twice' into 'master'

Resolve ""When this merge request is accepted, this issue will be closed automatically" rendered twice"

## What does this MR do?

1. Only show the above text when there is an MR that will close the issue, and even then, only show it once.
2. Apply 98f147e84d2bd8f2278452ac0852118452c76d4a to a bunch of other places that need it.

## Are there points in the code the reviewer needs to double check?

¯\_(ツ)_/¯

## Why was this MR needed?

Some pages were broken.

## What are the relevant issue numbers?

Fixes #18446.

## Screenshots (if relevant)

Before:
![image](/uploads/23cfaf95b7c798f22963ff67f78a803b/image.png)

After:
![image](/uploads/ca9c538069ba52e53858c69387738521/image.png)

## Does this MR meet the acceptance criteria?

- [ ] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- [ ] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [ ] API support added
- [ ] Tests
  - [ ] Added for this feature/bug
  - [ ] All builds are passing
- [ ] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [ ] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [ ] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !4594