macOS 12 runner image will be removed

Author: jan.nijtmans

.github/workflows/mac-build.yml

@@ -11,7 +11,7 @@ permissions:
   contents: read
 jobs:
   xcode:
-    runs-on: macos-12
+    runs-on: macos-13
     defaults:
       run:
         shell: bash
@@ -34,7 +34,7 @@ jobs:
           MAC_CI: 1
         timeout-minutes: 15
   clang:
-    runs-on: macos-12
+    runs-on: macos-13
     strategy:
       matrix:
         config: