py-nbformat: updated to 5.3.0

5.3.0
=====
- Use `f`astjsonschema`` by default
- Adopt ``pre-commit`` and auto-formatters
- Increase minimum ``jsonschema`` to 2.6, handle warnings

5.2.0
=====
- Add ability to capture validation errors
- Update supported python versions
- Ensure nbformat minor version is present when upgrading
- Only fix cell ID validation issues if asked
- Return the notebook when no conversion is needed
- Catch AttributeErrors stemming from ipython_genutils as ValidationErrors on read
- Don't list pytest-cov as a test dependency
- Remove dependency on IPython genutils
- Include tests in sdist but not wheel

(adam)