Create new test class for serialization tests or upstream to gufe? #1308
Description
Follow up from #1294
Our serialization tests subclass the GufeTokenizableTestsMixin but consistently overwrite the test_repr method to offer a little bit more testing than what the gufe base class offers.
Since we overwrite this method for nearly all protocol tests, we should either a) create a base test class with this overriden method here in openfe, or b) update the gufe test class to have this extra test functionality.