Drop Python 3.9 support

[emdneto]

Close #4887

[DylanRussell]

Looks like a bunch of checks are failing but otherwise this LGTM.. is there any official python lang document that describes what you can get rid of now that this version is deprecated ?

[emdneto]

Looks like a bunch of checks are failing but otherwise this LGTM.. is there any official python lang document that describes what you can get rid of now that this version is deprecated ?

@DylanRussell On top of my head, I remember mostly typing stuff like:

• int | str instead of Union[int, str]
• str | None instead of Optional[str]
• TypeAlias

For documentation, I believe: https://docs.python.org/3/whatsnew/3.10.html
We should leverage ruff UP rules to keep the codebase updated with the most recent syntax.

re failing tests: i need to update in -contrib and merge there first

[emdneto]

Had to pin those. sdk tests were failing for pypy