Removes Python 3.6

[staticdev]

• Remove Pyhon 3.6 references
• Cleanup appvoyer
• Python 3.9 becomes default version for pypy (by default it used 3.6)
• Python 3.10 becomes default version for flows

Closes #1075

[staticdev]

I'd rather get rid of .flake8 and put it all in setup.cfg or tox.ini but this works for now

Done, I switched back flake8 config to tox.ini. Could you change the required checks below?

• from test (pypy3, pypy, false) to Python tests / test (pypy3.9, pypy, false)
• from test (3.9, flake8,doclint,docs,commitlint, false) to Python tests / test (3.10, flake8,doclint,docs,commitlint, false)

[sigmavirus24]

Removed those. The new tests haven't run on main yet so can't add them yet. Merging this to get that going.