Hide tables in Users admin page if empty

What does this MR do and why?

This MR hides tabs that include no users to avoid requiring a scrollbar to see all tabs in cases where not all categories are used.

Comes from a large MR: !77593 (closed).

• related issue: Resolve "hidden" tabs visibility in Admin > Members list

Screenshots or screen recordings

Current view:

Proposed view:

Proposed view after an unused tab (blocked) is removed:

How to set up and validate locally

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

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.

spec/features/admin/users/users_spec.rb

@@ -75,7 +75,6 @@
     end
 
     describe 'tabs' do
-
       let_it_be(:tabs_user, reload: true) { create(:user) }
 
       it 'has Active tab' do