Updated styling commit SHA on branches page

## What does this MR do?

Updated styling of commit SHA on the branches page to include the commit icon and be blue

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


## Why was this MR needed?
to make the branches page in line with upcoming update to the commit list, which also styles the commit sha, but slightly different.

## Screenshots (if relevant)
before:
![image](/uploads/ce6eae30d0a07be2d76881d3c5e04e7d/image.png)

after:
![image](/uploads/a10df4fe6efbb168fc9b51ae87f53da7/image.png)


## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG.md) 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 [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [ ] 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 it does - rebase it please)
- [ ] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?

Closes #24022

See merge request !7219