GitLab CI: Don't run Black and Bandit in addition to Ruff
This is based on !1486 (merged), please review and merge that first.
Ruff replaces both Black [1] and Bandit [2]. Running those in addition to Ruff has no benefit and requires additional effort to ignore specific checks.
[1] https://docs.astral.sh/ruff/formatter/#black-compatibility
Edited by segfault