fix: Remove caching for pip in Python setup step

Author: marc-hanheide

.github/workflows/ci.yml

@@ -30,7 +30,6 @@ jobs:
         uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python-version }}
-          cache: pip
 
       - name: Run tests with coverage
         working-directory: backend