Run format on py@3.14

Author: schnellerhase

.github/workflows/spack-matrix.yml

@@ -17,7 +17,7 @@ jobs:
     steps:
       - uses: actions/setup-python@v6
         with:
-          python-version: '3.13'
+          python-version: '3.14'
       - uses: actions/checkout@v5
         with:
           fetch-depth: 2