* Use the total issue count for UI
This fixes a problem where the "All" line item on the Issues or Pull Requests page was only showing the count of the selected repos instead of the total of all issues/prs in all repos.
The "total number of shown issues" number is now stashed in a different context variable in case it wants to be used by the frontend later. It's currently not being used.
Fixes#20574
* Remove unused context variable
Co-authored-by: zeripath <art27@cantab.net>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>