OpenAPIDeserializer add seam for converting JsonNode to Object

[taylortails]

This PR does the following:

• OpenAPIDeserializer.java add seam allowing alternative ways to convertValues from JsonNodes. (TeaVM doesnt handler use of ObjectMapper)
• OpenAPIDeserializer.java use jsr310 consistently for date processing (TeaVM doesnt have Calendar.Builder)
• OpenAPIV31ParserSchemaTest.java changed so that the build also runs on windows

Background:
I'm using TeaVM to transpile the project into javascript. Minor changes were necessary to enable reduced use of jackson and use more common jdk apis which the transpiler supports.

[taylortails]

@micryc are you able to run the workflows?