[Docker] Fix broken production image (#6953)

* Check for presense of manage.py

* Fix directory copying

.github/workflows/docker.yaml

@@ -89,6 +89,7 @@ jobs:
           docker run --rm inventree-test invoke --list
           docker run --rm inventree-test gunicorn --version
           docker run --rm inventree-test pg_dump --version
+          docker run --rm inventree-test test -f /home/inventree/src/backend/InvenTree/manage.py
       - name: Build Docker Image
         # Build the development docker image (using docker-compose.yml)
         run: docker compose --project-directory . -f contrib/container/dev-docker-compose.yml build --no-cache

contrib/container/Dockerfile

@@ -33,6 +33,8 @@ ENV INVENTREE_MEDIA_ROOT="${INVENTREE_DATA_DIR}/media"
 ENV INVENTREE_BACKUP_DIR="${INVENTREE_DATA_DIR}/backup"
 ENV INVENTREE_PLUGIN_DIR="${INVENTREE_DATA_DIR}/plugins"
 
+ENV INVENTREE_BACKEND_DIR="${INVENTREE_HOME}/src/backend"
+
 # InvenTree configuration files
 ENV INVENTREE_CONFIG_FILE="${INVENTREE_DATA_DIR}/config.yaml"
 ENV INVENTREE_SECRET_KEY_FILE="${INVENTREE_DATA_DIR}/secret_key.txt"
@@ -122,10 +124,9 @@ ENV INVENTREE_COMMIT_DATE="${commit_date}"
 ENV PATH=/root/.local/bin:$PATH
 COPY --from=prebuild /root/.local /root/.local
 
-ENV INVENTREE_BACKEND_DIR="${INVENTREE_HOME}"
 
 # Copy source code
-COPY src/backend/InvenTree ./InvenTree
+COPY src/backend/InvenTree ${INVENTREE_HOME}/src/backend/InvenTree
 COPY --from=frontend ${INVENTREE_HOME}/src/backend/InvenTree/web/static/web ./src/backend/InvenTree/web/static/web
 
 # Launch the production server
@@ -133,8 +134,6 @@ CMD gunicorn -c ./gunicorn.conf.py InvenTree.wsgi -b 0.0.0.0:8000 --chdir ./Inve
 
 FROM inventree_base AS dev
 
-ENV INVENTREE_BACKEND_DIR="${INVENTREE_HOME}/src/backend"
-
 # Vite server (for local frontend development)
 EXPOSE 5173