Update AWS detector and instrumentation semconv to v1.21.0

[MrAlias]

Part of #4264

AWS semconv docs: https://github.com/open-telemetry/semantic-conventions/blob/main/docs/faas/aws-lambda.md

[codecov]

Codecov Report

Merging #4265 (71bade5) into main (0c4e5a9) will not change coverage.
The diff coverage is 100.0%.

@@          Coverage Diff          @@
##            main   #4265   +/-   ##
=====================================
  Coverage   79.4%   79.4%           
=====================================
  Files        166     166           
  Lines      10363   10363           
=====================================
  Hits        8233    8233           
  Misses      1996    1996           
  Partials     134     134           

Files Changed	Coverage
detectors/aws/ec2/ec2.go	ø
detectors/aws/ecs/ecs.go	ø
detectors/aws/eks/detector.go	ø
detectors/aws/lambda/detector.go	ø
...github.com/aws/aws-sdk-go-v2/otelaws/attributes.go	ø
...tation/github.com/aws/aws-sdk-go-v2/otelaws/aws.go	ø
...om/aws/aws-sdk-go-v2/otelaws/dynamodbattributes.go	ø
...hub.com/aws/aws-sdk-go-v2/otelaws/sqsattributes.go	ø
.../github.com/aws/aws-lambda-go/otellambda/lambda.go	100.0%