[cxf] add support for Swagger2 (#3668)

[fizzet]

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.
• Run the following to build the project and update samples:

  ./mvnw clean package 
  ./bin/generate-samples.sh ./bin/configs/*.yaml
  ./bin/utils/export_docs_generators.sh
  

  (For Windows users, please run the script in Git BASH)
  Commit all changed files.
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@bbdouglas @sreeshas @jfiala @lukoyanov @cbornet @jeff9finger @karismann @Zomzog @lwlee2608 @martin-mfg

[wing328]

thanks for the PR. can you please PM me via Slack for a quick chat when you've time?
https://join.slack.com/t/openapi-generator/shared_invite/zt-12jxxd7p2-XUeQM~4pzsU9x~eGLQqX2g

[fizzet]

Sorry, I'm not on Slack

[Harpune]

Thanks for this PR! Is there any update on the merge?

[wing328]

please resolve the merge conflicts and we will try to get it merged

[fwermelskirchen]

@wing328, unfortunately this PR is still not merged and @fizzet has no activity. Could we please merge #19954 instead?

[wing328]

#19954 is just an issue (not PR)

can you (or anyone) file a new PR on top of this one with resolved merge conflicts?

[fwermelskirchen]

reselved merge conflicts in #22010

[wing328]

@fwermelskirchen thanks. i'll get it reviwed and merged asap

[wing328]

closed via #22010