[ENH] Catch22 error handling for unimported pycatch22 module

[Moonzyyy]

What does this implement/fix? Explain your changes.

Currently when running pycatch22 within catch22 a error may occur if the user hasn't imported the module. Instead, a warning is shown that the user needs to install pycatch22 and allowing the algorithm to still run using default settings.

Does your contribution introduce a new dependency? If yes, which one?

Warnings. Though aeon library already has the dependency installed.