Support for XmlSchema JAXB annotation

Hello all,

does anything speak against supporting XmlSchema annotations during model resolution? We have in our projects the following setup:

1. Design data types in XSD files 

2. Generate Java POJOs annotated with JAXB annotations via xjc tool

3. Generate / Serve OAS files from annotated POJOs using springdoc (this uses swagger-core under the hood).

I notice that swagger-core does not read from the XmlSchema, which leads to missing information in the XML Object of the resulting OAS file.

Already created a PR to address this: https://github.com/swagger-api/swagger-core/pull/4278