Revert #29031

[ph]

This revert the code #29031 of the APM Instrumentation of the Elastic Agent.
To unblock the build of and the CI for other team. This would require
more investigation to really understand the problem.

Fixes elastic/fleet-server#1129

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• 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
• I have added an entry in CHANGELOG.next.asciidoc or CHANGELOG-developer.next.asciidoc.

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[elasticmachine]

Pinging @elastic/elastic-agent-control-plane (Team:Elastic-Agent-Control-Plane)

[mergify]

This pull request does not have a backport label. Could you fix it @ph? 🙏
To fixup this pull request, you need to add the backport labels for the needed
branches, such as:

• backport-v./d./d./d is the label to automatically backport to the 7./d branch. /d is the digit

NOTE: backport-skip has been added to this pull request.

[elasticmachine]

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• Reason: null

• Start Time: 2022-02-03T20:26:00.986+0000

• Duration: 364 min 47 sec

• Commit: fd9d388

Test stats 🧪

Test	Results
Failed	0
Passed	48115
Skipped	4292
Total	52407

💚 Flaky test report

Tests succeeded.

🤖 GitHub comments

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[ph]

@kvch Adding you to this PR as well, because when I've reverted the code for the instrumentation I had conflict with the configuration loading change.

[ph]

@michel-laterman I've fixed a linter issue from the diagnostic command, can you take a look at this specific part?

[ph]

@simitt fyi, I will check tomorrow with Stuart, but let's unblock people for now.

[blakerouse]

Tested this and it does fix the issue.