Resolve "Label autocomplete doesn't handle spaces after `~~`"

What does this MR do?

This cherrypicks the changes from !7129 (merged) that were missed in master for some strange reason.

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

We should check how this wasn't included.

Why was this MR needed?

Screenshots (if relevant)

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 #25964 (closed)