[Group Activity] Add "last updated" timestamp
Problem to solve
Under #325580 the Group Activity MR query was converted from being dynamic to 24-hour cached for performance reasons. That means the number displayed can be slightly out of date. This needs to be made clear to users.
Proposal
In the Group "Recent activity" metrics (example), add a "Last updated" timestamp for "Merge Requests opened" to show when the data was last collected.
Edited by Dan Jensen