Align MSRV and Stable CI Coverage (Including Doc Tests) #974
Description
Update MSRV to run the same checks and tests as stable, including doc tests, so both lanes are equivalent. To ensure the two don't drift apart, we probably will want to have the same matrix running both stable and MSRV. We should ensure doc tests are part of PR CI; everything currently being tested in either MSRV or stable currently should be tested in both after the changes.
Important: We should ensure doc tests are always run!