[Spring] add support for api versioning

[jpfinne]

Fix #22027 by adding an option version attribute to the @RequestMapping annotation.

Add springApiVersion configOption
Add x-spring-api-version vendorExtensions on operation to override or disable the default

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[wing328]

thanks for the Pr

quick question: why do you need to remove the extension? wouldn't the next line using putIfAbsent be enough?

[jpfinne]

My goal is to remove the version attribute per operation.

For example:

/help:
  get:
    x-spring-api-version: ''

generates:

   @RequestMapping(
        method = RequestMethod.GET,
        value = TestApi.PATH_GET_HELP
    )

I've fixed the implementation and the unit test.

[wing328]

👌

if no further question/feedback from anyone, i'll merge it later this week