Update Dockerfile to copy source code to the current directory with appuser ownership

Dockerfile

@@ -41,7 +41,7 @@ RUN python -m pip install --upgrade pip \
     && pip install -r requirements.txt
 
 # Copy the source code into the container.
-COPY --chown=appuser . $HOME/app
+COPY --chown=appuser . .
 
 # Expose the port that the application listens on.
 EXPOSE 7860