gh-actions wheels: macos-13 is deprecated

Author: mr-c

.github/workflows/wheels.yml

@@ -96,8 +96,10 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        # macos-13 is an intel runner, macos-14+ is apple silicon
-        os: [macos-13, macos-latest]
+        # macos-15-intel will be EOL in August 2027,
+        # https://github.com/actions/runner-images/issues/13045
+        # macos-14+ is apple silicon
+        os: [macos-15-intel, macos-latest]
     steps:
       - uses: actions/checkout@v5
         if: ${{ github.event_name != 'repository_dispatch' }}