NIFI-5105: Improvements for nifi-aws-bundle

[zenfenan]

Introduces the following improvements:

• The AWS SDK version has been updated to the latest release (1.11.319)
• Removed aws-java-sdk which packed unnecessary artifacts i.e. artifacts not used by the nifi-aws-bundle. The nifi-aws-nar now weights ~50 MB less

Test with S3 and it works well.

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[jvwing]

Reviewing...

[jvwing]

Thanks, @zenfenan, this looks good.

• Full build with contrib-check passes
• nifi-aws-processors integration tests pass
• Manual testing with an S3 flow worked fine

And great news that the NAR file is down to ~15 MB!