refactor(docker): Change python image + gcc

The previous python-alpine image was causing verry long build times
for the gcc compiler (which will be needed later)

ref:
sass/libsass-python#285
sass/libsass-python#282

Dockerfile

@@ -1,19 +1,22 @@
-FROM python:3.11-alpine AS build
+FROM python:3.11-slim AS build
 
 RUN pip install --no-cache-dir -U poetry
 
 COPY pyproject.toml poetry.lock ./
 RUN poetry export --with dev -f requirements.txt --output requirements.txt
 
-FROM python:3.11-alpine
+FROM python:3.11-slim
 
 ENV PATH=$PATH:/home/docker/.local/bin \
     PYTHONUNBUFFERED=1
 
 WORKDIR /project
 
-RUN adduser -D -g "docker" docker
+RUN adduser --gecos "docker" docker
 RUN chown -R docker:docker /project
+RUN apt update
+RUN apt install -y gcc
+
 USER docker
 
 COPY --from=build ./requirements.txt .