What does this MR do?
It makes rendering usernames case-insensitive.
Are there points in the code the reviewer needs to double check?
Non-lating usernames won't be covered by this fix for Ruby < 2.4.
Since username's validations don't let to use non-latin letters, I'm not sure this would be a problem.
Why was this MR needed?
It makes UX simpler.
Screenshots (if relevant)
Does this MR meet the acceptance criteria?
Changelog entry added, if necessary
API support added
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 #24493 (closed)