Exposes more information for check_output decorator errors

[skrawcz]

If the user does something that involves the mistyping target_ or tries to use a key word argument that doesn't map to a validator for the given output type, then the error will be cryptic. This adds context that it's for the check_output decorator and which function it's for.

Changes

• raises nicer error message for check_output issues.

How I tested this

• wrote unit test

Notes

Checklist

• PR has an informative and human-readable title (this will be pulled into the release notes)
• Changes are limited to a single goal (no scope creep)
• Code passed the pre-commit check & code is left cleaner/nicer than when first encountered.
• Any change in functionality is tested
• New functions are documented (with a description, list of inputs, and expected output)
• Placeholder code is flagged / future TODOs are captured in comments
• Project documentation has been updated if adding/changing functionality.