add write-all permission to workflow cache cleanup steps

.github/workflows/test-backend.yml

@@ -127,6 +127,7 @@ jobs:
     if: ${{ needs.files-changed.outputs.backend == 'true' || needs.files-changed.outputs.docker == 'true' }}
     needs: [files-changed, unit_test_backend]
     runs-on: ubuntu-latest
+    permissions: write-all
     continue-on-error: true
     steps:
       - name: Delete cache

.github/workflows/test-e2e.yml

@@ -101,6 +101,7 @@ jobs:
     name: Cleanup
     needs: [docker_preparation, fullstack_tests]
     runs-on: ubuntu-latest
+    permissions: write-all
     continue-on-error: true
     steps:
       - name: Delete cache

.github/workflows/test-webapp.yml

@@ -103,6 +103,7 @@ jobs:
     if: ${{ needs.files-changed.outputs.docker == 'true' || needs.files-changed.outputs.webapp == 'true' }}
     needs: [files-changed, unit_test_webapp]
     runs-on: ubuntu-latest
+    permissions: write-all
     continue-on-error: true
     steps:
       - name: Delete cache