Adds isShort + isUnboundedInteger to IJsonSchemaValidationProperties implementers

Created by: spacether

Adds isShort + isUnboundedInteger to IJsonSchemaValidationProperties implementers This allows CodegenModel CodegenResponse CodegenParameter CodegenResponse to be able to tell the difference in the templates between an int32 parameter and an unbounded integer parameter When merged, this will resolve https://github.com/OpenAPITools/openapi-generator/issues/9447#issuecomment-843366806

This is not a breaking change with fallback because isInteger behaves the same. If one needs to differentiate between int32 and unbounded integers, one should use the template variables:

• isShort
• isUnboundedInteger

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