Use the --break-system-packages when installing pipenv

Alpine Linux 3.20 configures Python 3 as externally managed, so we need
to pass this flag to `pip` to install a Python package directly. Since we
are using this to build a Python virtual environment in the
`compile-stage` that is moved to the `build-stage` for use in the final
image this should pose no issues.

Author: mcdonnnj

Dockerfile

@@ -51,7 +51,7 @@ COPY src/config.toml /root/.cargo/
 # Python virtual environment. This is done separately from the virtual
 # environment so that pipenv and its dependencies are not installed in the
 # Python virtual environment used in the final image.
-RUN python3 -m pip install --no-cache-dir --upgrade pipenv==${PYTHON_PIPENV_VERSION} \
+RUN python3 -m pip install --break-system-packages --no-cache-dir --upgrade pipenv==${PYTHON_PIPENV_VERSION} \
   # Manually create Python virtual environment for the final image
   && python3 -m venv ${VIRTUAL_ENV} \
   # Ensure the core Python packages are installed in the virtual environment