Refactor to use squash option feature spec
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The squash feature is currently split into 2 files. Should we combine them into one file?
**Current**
| Project Setting | MR Setting |
| ------ | ------ |
|`spec/features/projects/settings/user_manages_merge_requests_settings_spec.rb` | `spec/features/merge_request/user_edits_squash_commits_spec.rb` |
|  |  |
## Proposal
Because the squash is on 2 different pages, is it okay to put it in a combined file?
- ex. `squash_option`
Or should we create 2 separate independent squash files?
- ex `user_manages_squash_option_in_project_settings`
- ex `user_edit_squash_option_in_merge_request`
## Background Information
The following discussion from !35392 should be addressed:
- [ ] @a_mcdonald started a [discussion](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/35392#note_375477228):
> Since there are so many scenarios that are squash-related, should it be a separate file that is called accordingly - e.g. `user_edits_squash_settings_spec`? The fact that we have to have two `describe` within the same test seems quite strange to me.
>
> To make things worse, there is also `user_edits_mr_spec` in the same folder that makes it even more confusing. Perhaps it could be combined with that lonely `it 'changes the target branch'` that is outside of `describe 'Squash commits'`?
>
> Would be nice to have naming a bit more logical but I am not very familiar with this test suite so there might be some historic reasons for that. Leaving this up to you :slight_smile:
issue