Upgrade PHP mac runner to avoid slow PHP installs (#18972)

PiperOrigin-RevId: 682453854

Co-authored-by: Mike Kruskal <[email protected]>

Author: zhangskz

.github/workflows/test_php.yml

@@ -152,7 +152,7 @@ jobs:
       matrix:
         version: ['8.2']
     name: MacOS PHP ${{ matrix.version }}
-    runs-on: macos-12
+    runs-on: macos-13
     steps:
       - name: Checkout pending changes
         uses: protocolbuffers/protobuf-ci/checkout@v2