ci: set working directory for goveralls action

Author: pandatix

.github/workflows/integration.yaml

@@ -137,4 +137,5 @@ jobs:
       - name: Upload coverage to Coveralls
         uses: shogo82148/actions-goveralls@e6875f831db61e6abffbd8df91a2eb6cd24b46c9 # v1.9.1
         with:
-          path-to-profile: 'webserver/cov.out'
+          path-to-profile: 'cov.out'
+          working-directory: 'webserver'