really drop python<=3.7 support

[kloczek]

Filter all code over pyupgracde --py38-plus.

[kloczek]

BTW end of this month 3.8 will be EOSed.

[github-actions]

This pull request is stale because it has been open for 4 weeks with no activity. Remove stale label or comment or this will be closed in 2 weeks.

[kloczek]

Any update? 🤔

[jborean93]

Sorry I didn't get to this earlier. I'm reluctant to merging in stylistic changes without having an actual check in CI to back it for future commits. Granted there are still some Python 2-isms still in there that this PR is fixing but making these changes doesn't really achieve to much in the long run.

If I was really wanting to do something like this I would prefer to just have something like black to go over the codebase.

[kloczek]

black is the Python code formatter.
pyupgrade replaces syntax to more effective handled by exact Python version (please read pyupgrade documentation for details).
gssapi passes pytest test suite with this PR.
Did you test this PR? 🤔