fix(challenge): Stricter tests for "OOP: Constructor property"

[Greenheart]

Pre-Submission Checklist

• Your pull request targets the staging branch of freeCodeCamp.
• Branch starts with either fix/, feature/, or translate/ (e.g. fix/signin-issue)
• You have only one commit (if not, squash them into one commit).
• All new and existing tests pass the command npm test. Use git commit --amend to amend any fixes.

Type of Change

• Small bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds new functionality)
• Breaking change (fix or feature that would change existing functionality)
• Add new translation (feature adding new translations)

Checklist:

• Tested changes locally.
• Closes currently open issue (replace XXXX with an issue no): Progress [beta] QA of Object Oriented Programming Section #12966

Description

• Added a test case to ensure campers use Object.constructor rather than the instanceof operator.
• Also fixed an misleading sentence in the instruction.

Ref: #12966 (comment)

[no-stack-dub-sack]

EDIT: still LGTM, but after looking more closely, I have one minor suggestion 👇

[no-stack-dub-sack]

I've tested the changes locally and they work fine! However, I think we should also make the instructions a tad more clear, just to eliminate any possible confusion:

"Write a joinDogFraternity function that takes a candidate parameter and, using the constructor property, return true if the candidate is a Dog, otherwise return false."

Who knows, this may not be necessary, but I don't think it could hurt.

Thoughts @Greenheart?

[Greenheart]

@no-stack-dub-sack I like it, will add that right away! 😄