Merge pull request #9 from IBM/update_mac_runners

Remove macos-12, Add macos-15 runner

Author: Fryguy

.github/workflows/test.yml

@@ -204,9 +204,9 @@ jobs:
         - ubuntu-22.04
         - ubuntu-20.04
         - macos-latest
+        - macos-15
         - macos-14
         - macos-13
-        - macos-12
         - windows-latest
         - windows-2022
         - windows-2019