[ jaxrs-resteasy] fix java8 datetime issue

[autodidacticon]

Addresses #5584

updates jaxrs-resteasy pom and jaxrs-resteasy jacksonconfig templates

added samples for jaxrs-resteasy java8 server generation

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  ./bin/generate-samples.sh
  ./bin/utils/export_docs_generators.sh
  

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[autodidacticon]

@wing328 Latest build is failing on seemingly unrelated content. Is there a way to reexecute the build or have my changes somehow disturbed the failing sample?

[wing328]

Thanks for the PR but your commit (as shown in the Commits tab) is not linked to your Github account, which means this PR won't count as your contribution in https://github.com/OpenAPITools/openapi-generator/graphs/contributors.

Let me know if you need help fixing it.

Ref: https://github.com/OpenAPITools/openapi-generator/wiki/FAQ#how-can-i-update-commits-that-are-not-linked-to-my-github-account

[autodidacticon]

Good catch; fixed and thank you.

[wing328]

cc @bbdouglas (2017/07) @sreeshas (2017/08) @jfiala (2017/08) @lukoyanov (2017/09) @cbornet (2017/09) @jeff9finger (2018/01) @karismann (2019/03) @Zomzog (2019/04) @lwlee2608 (2019/10) @nmuesch (2021/01)