Try different exclude

Author: jeromekelleher

.github/workflows/ci.yml

@@ -27,7 +27,7 @@ jobs:
         exclude:
           # Just run macos tests on one Python version
           - os: macos-13
-            python-version: ["3.9", "3.11"]
+            python-version: "3.9"
     steps:
       - uses: actions/checkout@v4
       - name: Set up Python ${{ matrix.python-version }}