Summary
Enable code security scanning and update CI workflows.
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Contents ([109](https://github.com/octue/twined/pull/109))
Operations
- Add `codeql.yml` workflow to enable code-scanning
- Use new `octue/check-semantic-version` and `octue/generate-pull-request-description` GitHub actions
- Update versions of other GitHub actions used in workflows
Chores
- Upgrade `flake8` pre-commit hook
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