Use poetry for dependency management

Dockerfile

@@ -1,18 +1,11 @@
 FROM python:3.7-buster
 
-# Run project binaries from the user's local bin folder
-ENV PATH=/home/newsreader/.local/bin:$PATH
+RUN pip install poetry
 
-# Set the default shell
-RUN useradd -ms /bin/bash newsreader
-
-RUN mkdir /app
 WORKDIR /app
-RUN chown newsreader:newsreader /app
-USER newsreader
+COPY poetry.lock pyproject.toml /app/
 
-# Use a seperate layer for the project requirements
-COPY requirements /app/requirements
-RUN pip install --user -r requirements/dev.txt
+RUN poetry config virtualenvs.create false
+RUN poetry install --no-interaction
 
 COPY . /app/