Remove upper version pin for python from OAK

There are good reasons to avoid foundational libraries including defensive upper level pins, see:

https://github.com/linkml/linkml/pull/3675#pullrequestreview-4570277821

_Originally posted by @matentzn in https://github.com/INCATools/ontology-access-kit/pull/902#discussion_r3588720058_

Search the repository's dependency metadata for the upper Python version pin and read the surrounding configuration. Remove only that upper bound, then verify the resulting package metadata and run the dependency or installation checks available in the project; done means OAK no longer rejects newer Python versions because of this pin.

Written by the indexing model from the issue text.