new: first 3.x release
Changes:
- add support to custom 'out-of-package' MISP modules
- new extra '[all]' installs dependencies required by all modules
- default package installs only workflow-required dependencies
- remove all dependencies located in git repositories
- enforce single approach to discover package and file system modules
- add pre-commit hook to run black, isort, and flake8
- logging captures deprecation warnings
- flake8 linter runs against all modules
- remove custom module discovery logic when building the documentation
- remove all exported symbols where not needed
