Discriminator - Ensure warning shows up in recursive case

[gadcam]

Traverse paths until exhaustion of the tree before checking if a discriminator is needed.
With the previous code the example added in the test where we have a oneOf hidden inside an array would be enough to confuse the check.

[gadcam]

@microsoft-github-policy-service agree

[baywet]

Thank you for the contribution.
I do think we'll need to make a few tweaks before we can merge this.
Also, can you add an entry to the changelog please? (unreleased, changed)

[baywet]

this method name is confusing. An array would technically return true even though semantically it's not scalar.

Also the implementation checks two separate concerns: the structure (object) and the location (reference) of the schema.