Resolve "Buttons in the "Branches" page are stacking on top of each other depending on the selected filter"

What does this MR do?

Prevents the header controls on the branches page from bunching up when they take up more than 50% of the available screen width.

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

nope, pretty straight forward

Why was this MR needed?

see above

Screenshots (if relevant)

Before ($screen-lg)

After ($screen-lg)

Before ($screen-xs)

After ($screen-xs)

Does this MR meet the acceptance criteria?

• Changelog entry added
• Documentation created/updated
• API support added
• 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 it does - rebase it please)
• Squashed related commits together

What are the relevant issue numbers?

Closes #24820 (closed)