[kotlin-spring] Add beanQualifiers switch to populate RestController / Controller annotations with FQCN

[vlsergey]

PR checklist

• Read the contribution guidelines.
• Pull Request title clearly describes the work in the pull request and Pull Request description provides details about how to validate the work. Missing information here may result in delayed response from the community.
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  ./mvnw clean package 
  ./bin/generate-samples.sh
  ./bin/utils/export_docs_generators.sh
  

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P.S.: Yes, i do understand that indented behaviour can be archived using customized templates (and we are using them right now). But i feel that this setting is a solution to quite common problem and may be other Spring-based generators (including Java) shall have this option as well.

[wing328]

Tested the new option and the result is good.