Openapi gen cli improvements

[ecostanzi]

Fix #10510 .

1. add openapi generator cli command to npm scripts
2. update to openapi-generator-cli 1.0.8-4.2.2
3. feign client configuration excluded via FilterType.REGEX

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[avdev4j]

hi @ecostanzi,
great job !
I would like to review this PR, I hope tomorrow or this weeks during lunch time. Stay tuned ;)

[DanielFran]

@avdev4j @cbornet Did you have time to review it?

[avdev4j]

LGTM

Tested with both old and new version. The improvements are great. Remove the ExcludeComponentScan for using filter and avoid to call the openapi jar.

I suggest to merge this PR now and do another PR to upgrade the openapi generator later if we don't have enough time now.

This PR has been open for too long (my fault) ;)

[DanielFran]

@ecostanzi Are you expecting to update the generator version soon or can this be merged?

[ecostanzi]

@DanielFran yes I'll do it before merge

[DanielFran]

Thanks @ecostanzi