VSA: Add end event timestamp to table

Release notes

Several enhancements have been made to the VSA stage table, including the addition of a column for the last workflow event.

Problem

Currently, the VSA table can only be sorted by duration (time). There is no way clear option to sort by the date. users can't understand the sorting logic.

Proposal

1. Remove the sorting option from the title column.
2. Add an additional column called Last event to the VSA issues / MRs tables.
3. That new column will sort=end_event.
4. Tables default sorts by end_event (same as today).
5. Both project and group VSA need that fix.