Reset dropdown list when clicking filter input

What does this MR do?

Fixes an issue with the previous fix for the prevention of adding multiple filters

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

Not really. See if it's the best solution

Why was this MR needed?

The previous MR https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/9406 introduced a fix to prevent multiple filters of the same type but it worked if you use only the keyboard. If the user uses the mouse to click on the filter input the options were incorrect.

Screenshots (if relevant)

Before

After

Does this MR meet the acceptance criteria?

• Tests
  • 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 https://gitlab.com/gitlab-org/gitlab-ce/issues/28463