feat: allow for custom registry

This patch adds a simple CLI which can mirror all the images needed
as well as allow for simple override for `atmosphere_image_repository`
for all images.
diff --git a/Dockerfile b/Dockerfile
index e89fbd4..d9468a7 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -14,9 +14,9 @@
 ADD poetry.lock /app
 ADD pyproject.toml /app
 ENV POETRY_VIRTUALENVS_IN_PROJECT=true
-RUN poetry install --only main --no-root --no-interaction
+RUN poetry install --only main --extras operator --no-root --no-interaction
 ADD . /app
-RUN poetry install --only main --no-interaction
+RUN poetry install --only main --extras operator --no-interaction
 
 FROM python:3.10-slim AS kubectl
 ADD https://dl.k8s.io/release/v1.26.0/bin/linux/amd64/kubectl /kubectl