Fix coverage workflow

Author: robbievanleeuwen

.github/workflows/tests.yml

@@ -130,7 +130,7 @@ jobs:
       - name: Set up Python
         uses: actions/setup-python@v5
         with:
-          python-version: "3.11"
+          python-version: "3.12"
 
       - name: Upgrade pip
         run: |