std.MultiArrayList: add functions `addOne`, `pop`, and `popOrNull` (#11553)

Update basic usage test to account for these, and by extension for addOneAssumeCapacity.
609896a6e8InKryption committed on 4/30/2022, 2:51:53 AM· committed by GitHubparentcc39d45
1 file changedLine totals unavailable