Bug update aws sync async client handler instrumentation

[videnkz]

closes #3372

Checklist

• This is a bugfix
  • I have updated CHANGELOG.asciidoc
  • I have added tests that would fail without this fix

[github-actions]

👋 @videnkz Thanks a lot for your contribution!

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[videnkz]

@JonasKunz hi, I see that you have also opened a PR. If you see fit, you can close this PR.

[JonasKunz]

Hi @videnkz , looks like we've accidentally been working on this in parallel, but took different approaches.

I also thought about accessing the clientConfiguration field reflectively, but decided against it because the good old Field.setAccessible is not guaranteed to always work since Java 9:

If the aws-sdk is loaded in a Java Module (not the unnamed module as it is the case in the tests), the JVM will not allow reflective access to the field from Classloader of the advice class by default. There is a way around this, namely using Lookup.privateLookupIn after "opening" the target module via Instrumentation.redefineModule.

I've implemented a PoC for this "legal" reflection access here, just in case you are curious.

However, I decided that it is not worth introducing this for this fix yet and instead simply instrumented the constructors.

So closing this in favour of #3373 .