Add CI/CD linting checks

[sitzz]

Repo should have some linting checks in place:

• ruff check
• ruff format --check
• flake8 ?
• pylint ?
• bandit ?
• mypy ?
• safety or dependabot ?

All checks to be performed on pull requests and must successful run as a precondition for merging a PR.

[sitzz]

Currently code complies with ruff checks and formatting, as well as mypy.

Still considering flake8, pylint and bandit .. not sure what would be gained there...

Using safety is deemed unnecessary, and dependabot has already been enabled. Seeing as there's just a single dependency (Couchbase) defined as >=4.0.0 there shouldn't really be any issues.

[sitzz]

The tests currently implemented using pytest are being run as part of pre-commit hook (by me...) hence testing with Github Actions not strictly necessary.
Removing from milestone for v0.1.0.