Configure coverage testing profile

[firelizzard18]

The coverage testing profile should be configurable in the same manner as other kinds of testing profiles. From an outside perspective this seems like it should be a simple matter of adding a menu to the coverage run button.

Rationale: When I execute go test there's a -coverpkg flag I can pass to control the scope of what code gets instrumented for coverage. In some cases it's natural to show coverage for the entire project, where in other cases it's natural to show coverage only for a single package.

[firelizzard18]

CC @connor4312