Fix filters presence check to take value into consideration

What does this MR do and why?

This fixes a bug in the issues/MRs dashboard filter check which allows filtering by empty value. It can result to SQL statement timeout.

The fix is to check if the value of the filter is present. If not, the dashboard will show the "Please select at least one filter to see results" message.

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

1. View issues/MRs dashboard via http://gdk.test:3000/dashboard/issues or http://gdk.test:3000/dashboard/merge_requests.
2. Set a filter with no value (e.g. Assignee).
3. The Please select at least one filter to see results message should show up.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #353992