Fix up sync-crls script and add to Dockerfile.

- Fix some python formatting and import issues
- Fix dockerfile to include sync-crls script
- Adjust sync-crls script to use paths and CLI tools available in the
  Docker container

Dockerfile

@@ -79,6 +79,7 @@ COPY --from=builder /install/config/ ./config/
 COPY --from=builder /install/templates/ ./templates/
 COPY --from=builder /install/translations.yaml .
 COPY --from=builder /install/script/seed_roles.py ./script/seed_roles.py
+COPY --from=builder /install/script/sync-crls ./script/sync-crls
 COPY --from=builder /install/static/ ./static/
 COPY --from=builder /install/uwsgi.ini .
 COPY --from=builder /usr/local/bin/uwsgi /usr/local/bin/uwsgi