AWS SDK instrumentation for S3 and DynamoDB

[AlexanderWert]

What does this PR do?

Instrumentation for AWS SDK covering S3 and DynamoDB

Closes #1636
Closes #1637

Checklist

• This is a new plugin
  • I have updated CHANGELOG.asciidoc
  • My code follows the style guidelines of this project
  • I have made corresponding changes to the documentation
  • I have added tests that prove my fix is effective or that my feature works
  • New and existing unit tests pass locally with my changes
  • I have updated supported-technologies.asciidoc
  • Added an API method or config option? Document in which version this will be introduced
  • Added an instrumentation plugin? Describe how you made sure that old, non-supported versions are not instrumented by accident.

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• Start Time: 2022-05-06T06:01:22.867+0000

• Duration: 54 min 36 sec

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Test	Results
Failed	0
Passed	2869
Skipped	22
Total	2891

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[jackshirazi]

Although unlikely, there could be concurrent calls that would create multiple instances, which could produce different threads using different req-table maps. This would quickly be resolved for subsequent requests, so it is only a matter of some odd initial reqs being handled incorrectly in the worst case. So can leave it like this, especially if the lazy initialization is deliberate. An alternative is to initialize at class initialization time

[AlexanderWert]

I think having the lazy initialization is good to not allocate unnecessary memory in case certain parts of the SDK are not used at all (e.g. S3 but not DynamoDB).
Regarding race, I agree that it's possible but very unlikely and also not a big problem when it occurs. And actually we do the same in other plugins already. I think introducing a synchronized block is not worth the benefit compared to the performance impact. So I would leave it as is.

[jackshirazi]

nice!