[9.2](backport #47444) Move beatsauth extension to beats repo

[mergify]

Proposed commit message

This PR moves beatsauth extension from https://github.com/elastic/opentelemetry-collector-components to beats repo,

Checklist

• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have made corresponding change to the default configuration files
• I have added tests that prove my fix is effective or that my feature works. Where relevant, I have used the stresstest.sh script to run them under stress conditions and race detector to verify their stability.
• I have added an entry in ./changelog/fragments using the changelog tool.

Disruptive User Impact

None

Related issues

• Part of work for [Beats receivers] Add exporter translation support for all currently unsupported Elasticsearch output features #46749

  ---

  This is an automatic backport of pull request Move beatsauth extension to beats repo #47444 done by Mergify.

[mergify]

Cherry-pick of 68257d9 has failed:

On branch mergify/bp/9.2/pr-47444
Your branch is up to date with 'origin/9.2'.

You are currently cherry-picking commit 68257d99f.
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  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   NOTICE.txt
	modified:   go.mod
	modified:   go.sum
	deleted:    libbeat/otelbeat/oteltest/beatsauth_test.go
	modified:   x-pack/libbeat/common/otelbeat/otel.go
	new file:   x-pack/otel/extension/beatsauthextension/authenticator.go
	new file:   x-pack/otel/extension/beatsauthextension/authenticator_test.go
	new file:   x-pack/otel/extension/beatsauthextension/config.go
	new file:   x-pack/otel/extension/beatsauthextension/factory.go

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

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

[github-actions]

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