Deprecate and replace passlib

[kurtmckee]

The crypt module will be removed in Python 3.13.

However, the optional passlib package (used for PasswordType) uses the crypt module, but hasn't been updated in several years. It appears that there is not a path forward with passlib.

The immediate need is to silence the deprecation warnings in the sqlalchemy-utils test suite, but it will soon be necessary to completely remove passlib as an optional dependency.