UX: arrow instead of check sign

What does this MR do?

Fixes #22499 (closed): Uses fa-right-arrow instead of fa-check as the current build indicator in the build sidebar for better UX.

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

I don't think so

Why was this MR needed?

Better user experience

Screenshots (if relevant)

Before:

After:

Does this MR meet the acceptance criteria?

• CHANGELOG entry added
• Documentation created/updated
• API support added - not relevant
• Tests
  • Added for this feature/bug
  • All builds are passing
• Conform by the merge request performance guides
• Conform by the style guides
• Branch has no merge conflicts with master (if you do - rebase it please)
• Squashed related commits together

What are the relevant issue numbers?

#22499 (closed)