Test python 3.12

See merge request !10

Those versions have been end-of-life for some time

Move from setup.py to pyproject.toml

See merge request !13

Allow to use Oauth 2.0 tokens as well as personal/group/project token.

Replace cgi with email as suggested in https://peps.python.org/pep-0594/#cgi

Use OAuth-compliant headers for access token

See merge request !14