Added Instrumentation for ServletContainerInitializer#onStartup

[tobiasstadler]

What does this PR do?

Improves service name and version auto detection

Checklist

• This is an enhancement of existing features, or a new feature in existing plugins
  • I have updated CHANGELOG.asciidoc
  • I have added tests that prove my fix is effective or that my feature works
  • Added an API method or config option? Document in which version this will be introduced
  • I have made corresponding changes to the documentation

[github-actions]

👋 @tobiasstadler Thanks a lot for your contribution!

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[ghost]

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• Start Time: 2022-02-10T08:45:06.860+0000

• Duration: 53 min 5 sec

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Test	Results
Failed	0
Passed	2495
Skipped	16
Total	2511

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[eyalkoren]

@felixbarny asking for your review as there seem to be quite a lot of prior context leading to this

[tobiasstadler]

@felixbarny It might makes sense to include this in 1.29.0 release, toghter with the other service name/version auto detection.

[felixbarny]

Maybe you could find a better name for this. Don't hesitate to renaming InitServiceNameInstrumentation or creating a dedicated package for both.

[tobiasstadler]

Done, I hope it is ok now.

[felixbarny]

Sorry for all the nitpicks.

[felixbarny]

/run elasticsearch-ci/docs

[tobiasstadler]

Thank You!