[skip ci] Fix macos nightly version for older branches

Author: iluuu1994

.github/workflows/nightly.yml

@@ -234,7 +234,7 @@ jobs:
         debug: [true, false]
         zts: [true, false]
     name: "${{ matrix.branch.name }}_MACOS_${{ matrix.debug && 'DEBUG' || 'RELEASE' }}_${{ matrix.zts && 'ZTS' || 'NTS' }}"
-    runs-on: macos-13
+    runs-on: macos-${{ matrix.branch.version.minor >= 4 && '13' || '12' }}
     steps:
       - name: git checkout
         uses: actions/checkout@v4