Add column sorting to tables

Problem

Currently we use a drop down with sorting behavior. However this is not easy to understand and has unnecessary complexity.

Concerns

1. Moving the sorting feature to column headings will cause problems because there are more sortable options in the drop down than columns.
2. Can we iterate on this to something a bit smaller in scope.
   • does an MVC allow for current column sorting as well as drop down sorting
   • does this cause conflicts in the display behavior?
   • what is the accessibility concern in having sorting in 2 different locations.
     • does it have to be all or none?
3. What are the mobile screen views/behaviors
   • Bootstrap on mobile
4. where does a the data for customized columns live for the user once they are changed?
5. sortable versus non sortable columns
   • should all columns be sortable. (yes?)
   • what's needed to make that work.

Proposal

✏️ Previous work on Admin -> Users screen

✏️ Current Figma work file

I would like to propose an improvement to table column sorting around the idea of a table builder. This would allow a user to build a table with values they need. This would be the foundation to build for a more modern table sorting behavior. See related issue: gitlab-design#770 (closed)

Building	sorting