Fix python dependency detection

.forgejo/workflows/testing.yml

@@ -14,11 +14,9 @@ jobs:
         with:
           python-version: '3.11'
           cache: 'pip'
-      - name: Install needed python modules
-        working-directory: core
-        run: cd core && pip3 install -r requirements.prod.txt
+          cache-dependency-path: 'core/requirements.prod.txt'
       - name: Run django tests
-        working-directory: core
+        working-directory: /workspace/c3lf/c3lf-system-3/core
         run: python3 -m manage.py test
 
   deploy: