RJS-2858: Allow both internal and public name in realm::Results::{sort, distinct}

[kneth]

What, How & Why?

From the RJS ticket:

When mapTo is used to have an alias for a property name, Realm.Results.sorted() doesn't recognize the alias leading to errors like Cannot sort on key path 'NAME': property 'PersonObject.NAME' does not exist.

This closes realm/realm-js#6779

☑️ ToDos

• 📝 Changelog update
• 🚦 Tests (or not relevant)
• [ ] C-API, if public C++ API changed
• [ ] bindgen/spec.yml, if public C++ API changed