Flasksimpleauth

- test with python 3.8 to 3.11 and pypy 3.8 and 3.9
- add `FSA_REJECT_UNEXPECTED_PARAM` directive
- add special parameters for `Request`, `Session` and `Globals`
- require **Flask 2.2**
- improve `Reference` locking

This release:
- adds early sanity checks about path parameters: they *must* appear as function
parameters and should not have a default value.
- path parameters converter, if declared, should be consistent with
the corresponding parameter type.
- improve `mypy` checks by removing some *ignore* hints.
- improve `Makefile`.
- rename FSA generated exceptions: `ErrorResponse` and `ConfigError`.
- add `pymarkdown` check.
- add a GitHub CI configuration (with 99% coverage for now).