Use new Apple runner, and remove runner with impending deprecation

[mborland]

No description provided.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.5%. Comparing base (e8870b2) to head (a8410c1).
⚠️ Report is 2 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff           @@
##           develop   #1341   +/-   ##
=======================================
  Coverage     98.5%   98.5%           
=======================================
  Files          282     282           
  Lines        22550   22550           
  Branches      1960    1960           
=======================================
  Hits         22197   22197           
  Misses         353     353           

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