Autocomplete group members in group issues search author and assignee filters

What does this MR do?

Display group and nested group and project members in the group issues search author and assignee filters

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

  • SQL performance

Why was this MR needed?

All users are displayed in the group issues search author and assignee filters. It is inconvenient.

Does this MR meet the acceptance criteria?

What are the relevant issue numbers?

Closes #36702

Edited by username-removed-7736