Antora3 and node 16

[ludans]

Thanks for contributing!

Please check if the PR fulfills these requirements 👌:

• [x] Confirm the PR related to a dedicated issue
• [ ] Confirm your PR corrects a single bug or implements a single feature <= NO, antora 3 + node 16
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• [x] Your code is fully tested: 99% to 100% coverage
• [x] Everything is correct on Sonar dashboard
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• [x] Confirm license and copyright content is created/updated in each file (see CONTRIBUTING.md)
• [x] Confirm changelog.adoc is updated
• [x] If corrects vulnerabilities, confirm changelog.adoc contains CVE IDs

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Indicate related issue:

issue #189

Explain what is done, scope, limitations etc.

switch antora 2 to 3 (doc generation) switch to node 16

Does this PR introduce a breaking change? 😁

who knows