[8.4](backport #32921) Refactor endpoint resolver for AWS services

[mergify]

This is an automatic backport of pull request #32921 done by Mergify.
Cherry-pick of d0bc413 has failed:

On branch mergify/bp/8.4/pr-32921
Your branch is up to date with 'origin/8.4'.

You are currently cherry-picking commit d0bc413a50.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   CHANGELOG.next.asciidoc
	modified:   x-pack/filebeat/docs/inputs/input-aws-s3.asciidoc
	modified:   x-pack/filebeat/input/awscloudwatch/input.go
	modified:   x-pack/filebeat/input/awss3/input.go
	modified:   x-pack/filebeat/input/awss3/input_integration_test.go
	modified:   x-pack/libbeat/autodiscover/providers/aws/ec2/provider.go
	modified:   x-pack/libbeat/autodiscover/providers/aws/elb/provider.go
	modified:   x-pack/libbeat/docs/aws-credentials-config.asciidoc
	modified:   x-pack/metricbeat/module/aws/aws.go
	modified:   x-pack/metricbeat/module/aws/billing/billing.go
	modified:   x-pack/metricbeat/module/aws/cloudwatch/cloudwatch.go
	modified:   x-pack/metricbeat/module/aws/cloudwatch/metadata.go
	modified:   x-pack/metricbeat/module/aws/cloudwatch/metadata/ec2/ec2.go
	modified:   x-pack/metricbeat/module/aws/cloudwatch/metadata/rds/rds.go
	modified:   x-pack/metricbeat/module/aws/cloudwatch/metadata/sqs/sqs.go

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   x-pack/libbeat/common/aws/credentials.go
	both modified:   x-pack/libbeat/common/aws/credentials_test.go

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/github/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

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• Start Time: 2022-09-08T03:31:10.038+0000

• Duration: 133 min 55 sec

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Total	9101

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