Test on macos-13

Author: pgleeson

.github/workflows/main.yml

@@ -21,7 +21,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-latest, macos-latest, windows-latest]
+        os: [ubuntu-latest, macos-latest, macos-13, windows-latest]
         python-version: ["3.8", "3.9", "3.10", "3.11"]
 
     steps: