Add Python 3.10 and 3.11 to the testing

[cclauss]

DeprecationWarning:

/usr/local/lib/python3.12/site-packages/libfuturize/fixer_util.py:11:
  DeprecationWarning: lib2to3 package is deprecated and may not be able to parse Python 3.10+
    from lib2to3.fixer_util import (FromImport, Newline, is_import,

---

On Python 3.12...

=================================== FAILURES ===================================
___________ TestIsInstanceIsSubclass.test_isinstance_recursion_limit ___________

self = <test_future.test_isinstance.TestIsInstanceIsSubclass testMethod=test_isinstance_recursion_limit>

    def test_isinstance_recursion_limit(self):
        # make sure that issubclass raises RuntimeError before the C stack is
        # blown
>       self.assertRaises(RuntimeError, blowstack, isinstance, '', str)
E       AssertionError: RuntimeError not raised by blowstack

tests/test_future/test_isinstance.py:275: AssertionError
____________ TestIsInstanceIsSubclass.test_subclass_recursion_limit ____________

self = <test_future.test_isinstance.TestIsInstanceIsSubclass testMethod=test_subclass_recursion_limit>

    def test_subclass_recursion_limit(self):
        # make sure that issubclass raises RuntimeError before the C stack is
        # blown
>       self.assertRaises(RuntimeError, blowstack, issubclass, str, str)
E       AssertionError: RuntimeError not raised by blowstack

tests/test_future/test_isinstance.py:270: AssertionError