Improve the test & example submission files for Claims

As a developer, I want to improve the example data so that the files are easier to use internally and we have more clarity on what validation records may be testing, saving us testing time.

A few ideas on how to do this would be to:

• Smaller files (less records)

• Leverage the comments fields to identify tests

https://en.wikipedia.org/wiki/Minimal_reproducible_example