macos-13 GitHub runner deprecated, upgrading to macos-15 as per GitHub

recommendations

Author: agentmorris

.github/workflows/python_tests.yml

@@ -12,7 +12,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-latest, macos-13, windows-latest]
+        os: [ubuntu-latest, macos-15, windows-latest]
         python-version: ['3.9', '3.10', '3.11', '3.12']
     steps:
       - name: Checkout repository