Fix Example Serialization

[hinthornw]

(slightly breaking for comparison flows for unit testing)

1. Update the ID representation to mostly match the pytest format of path/to/test_file.py::test_function[arg#-arg#-arg#] instead of
2. Fallback to repr of object fo rexample inputs/outputs

Why?

• In unit testing, the example inputs/outputs are less important. Want to permit non-serializable objects.
• Don't want to keep creating populating new examples with new IDs just because the non-serializable object includes its memory ID in its repr