protein-translation: update tests to v1.1.0

The [test suite](https://github.com/exercism/python/blob/master/exercises/protein-translation/protein_translation_test.py) for protein-translation is out of date and needs updated to conform to the [latest canonical data](https://github.com/exercism/problem-specifications/blob/master/exercises/protein-translation/canonical-data.json).

