fix: Install ffmpeg prior to changing user

Dockerfile

@@ -7,13 +7,13 @@ WORKDIR /code
 
 COPY ./requirements.txt /code/requirements.txt
 
+RUN apt update && apt install -y ffmpeg
+RUN pip install --no-cache-dir --upgrade -r /code/requirements.txt
+
 RUN useradd -m -u 1000 user
 
 USER user
 
-RUN apt update && apt install -y ffmpeg
-RUN pip install --no-cache-dir --upgrade -r /code/requirements.txt
-
 ENV HOME=/home/user
 ENV PATH=/home/user/.local/bin:$PATH