sys.implementation's version should be GraalPy's version

[henryiii]

The way to get GraalPy's version should be sys.implementation.version, but for some reason GraalPy 24.1.0 returns sys.version_info instead (3.11.7.alpha), which isn't helpful. This is supposed to be the implementation version. For example, on PyPy 7.3.11:

>>>> import sys
>>>> sys.implementation.version
sys.pypy_version_info(major=7, minor=3, micro=11, releaselevel='final', serial=0)
>>>> sys.version_info
sys.version_info(major=3, minor=9, micro=16, releaselevel='final', serial=0)

This should be a named tuple for sys.implementation.version, and a hex for sys.implementation.hexversion.
See pybind/pybind11#5586.

As a workaround, __graalpython__.get_graalvm_version() gives the version as a string.