WIP: Adds requirements that supports anything in sha params

What does this MR do?

Fix the 404 error in API when the branch has a dot in its name as stated in #26561 (moved) and in #2709 (moved).

Why was this MR needed?

Since we use Grape gem, every param we define for a given endpoint is restricted to a default format. This default format does not allow dots in value, so whenever we have a :sha param we are going to explicitly allow any kind of text for it to work. This has been already done for some endpoints, so I just replicated the strategy for the other cases.

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• API support added
• Tests added for this feature/bug
• Review
  • Has been reviewed by UX
  • Has been reviewed by Frontend
  • Has been reviewed by Backend
  • Has been reviewed by Database
• Conform by the merge request performance guides
• Conform by the style guides
• Squashed related commits together

What are the relevant issue numbers?

Closes #26561 (moved), #2709 (moved)