Improve API key retrieval logic in Dockerfile for better handling of existing remote

Dockerfile

@@ -15,7 +15,7 @@ RUN pip install --no-cache-dir --upgrade -r requirements.txt
 COPY --chown=user . /app
 
 RUN --mount=type=secret,id=APIKey,mode=0444,required=true \
- git init && \
- git remote add origin $(cat /run/secrets/APIKey)
+    git init && \
+    (git remote get-url origin || git remote add origin $(cat /run/secrets/APIKey))
 
 CMD ["uvicorn", "app:app", "--host", "0.0.0.0", "--port", "7860"]