DEP: Python 3.11 Support

[snowman2]

https://scientific-python.org/specs/spec-0000/

Support for Python 3.11 ends in 2025 - Quarter 4.

[djhoese]

Unless I've missed the timing on this, Q4 2025 is October but Pyproj 3.8.0 is likely planned for September. How about we move this issue to a 3.8.1 or 3.9.0 milestone?

[snowman2]

It would be fine to delay this until after the 3.8 release.