Fixes Pipeline list commit column width should be adjusted
## What does this MR do?
- Fixes some HTML problems
- Pipeline and Build tables were inside an `ul` tag
- Pipeline table had 2 `tbody` tags and no `thead`
- Adds grid classes in Pipeline table in order to be responsive: The content of the last column was being hidden but the column it self was not which results in a lot of blank space
- Adds a percentage width to the commit column in the Pipeline table.
- Removes one level of nesting in the commit column in the Pipeline table and to the Build column in the Build table.
## Are there points in the code the reviewer needs to double check?
No
## Why was this MR needed?
The commit column had to much white space.
## Screenshots (if relevant)
![pipelines](/uploads/d198f07dceb498cc7ec537842cd34fff/pipelines.png)
## Does this MR meet the acceptance criteria?
- [x] [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
- [x] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)
## What are the relevant issue numbers?
Closes#22509
See merge request !6595