Add tests for #5393

[victornoel]

This is a repro for #5393.

It works on 2.18 but does not work on 2.19+, it fails with this error:

org.opentest4j.AssertionFailedError: 
Expected :[normalProperty, renamedProperty]
Actual   :[myProperties, normalProperty, renamedProperty]

[cowtowncoder]

Makes sense: just one request -- could you instead create separate test class like GenerateSchema5393Test? I know sometimes we add methods to existing classes, other times not. But in this case new one seems preferable as NewSchemaTest is growing and jsonschema package is pretty empty.

[cowtowncoder]

Thank you @victornoel ! @JooHyukKim provided #5404 based on this, so I merged that PR which also had the fix, so closing this PR.

[victornoel]

Thanks @cowtowncoder @JooHyukKim!