flake8, mypy, CI
Ensure source code passes flake8, mypy, and uses a CI to test these on merge to master.
GitLab upgrade completed. Current version is 18.3.6
https://about.gitlab.com/releases/2025/07/17/gitlab-18-2-released/
https://about.gitlab.com/releases/2025/08/21/gitlab-18-3-released/
Ensure source code passes flake8, mypy, and uses a CI to test these on merge to master.