Use LooseVersion from looseversion rather than distutils

[shaunc]

Using pytest-cases in python 3.11 results in a long string of deprecation warnings due to use of distutils.LooseVersion. This patch uses LooseVersion from "looseversion" package, which is designed to be a drop-in replacement without the deprecation warning.

[jayqi]

Noting that I've opened PR #312 which is an alternative approach to addressing the problem that this PR solves. Since pytest-cases is just comparing version specifications of the pytest package, which are all compliant with PEP 440, using LooseVersion is not needed and the more standard packaging.version.Version is sufficient.

The documentation from the looseversion package itself states:

If you are simply comparing versions of Python packages, consider moving to packaging.version.Version, which follows PEP-440. LooseVersion is better suited to interacting with heterogeneous version schemes that do not follow PEP-440.

[smarie]

Thanks to both of you @shaunc and @jayqi ! And sorry for the wait, last few months were crazy.
I will be in favor of following what is suggested in the doc, so @jayqi 's proposal in #312. @jayqi could you please pull the latest develop branch so that we can run against all python versions using nox+virtualenv?
If there is any problem with the legacy python versions, then we can reconsider @shaunc 's proposal.
Once again thanks a lot and sorry for the long wait !

[smarie]

Superseded by #312
Thanks again @shaunc !