Update Dockerfile

Dockerfile

@@ -1,17 +1,15 @@
 FROM python:3.9
 
 RUN useradd -m -u 1000 user
+USER user
+ENV PATH="/home/user/.local/bin:$PATH"
+# ^ when run as `user`, pip installs executables there
 
 WORKDIR /app
 
-COPY ./requirements.txt requirements.txt
-
+COPY --chown=user ./requirements.txt requirements.txt
 RUN pip install --no-cache-dir --upgrade -r requirements.txt
 
-COPY . /app
-
-RUN chown -R user:user /app
-
-USER user
+COPY --chown=user . /app
 
 CMD ["uvicorn", "app:app", "--host", "0.0.0.0", "--port", "7860"]