* Rework Match.group handling
Standardize group(), groups(), groupdict(), and __getattr__() to return
Any instead of AnyStr. Also special case group(0) and __getattr__(0) to
always return AnyStr. Use PEP 604 for unions in changed lines.
Eliminated the use of "bare" TypeVars (i.e. a TypeVar that appears only once) within generic methods. While not considered an error in PEP 484, these are a common source of bugs in code, and some type checkers (including pytype and pyright) flag them as errors.
Co-authored-by: Eric Traut <erictr@microsoft.com>
