Removed observer.version_major

[tobiasstadler]

Motivation/summary

Fixes #7387

Checklist

• Update CHANGELOG.asciidoc
• Update package changelog.yml (only if changes to apmpackage have been made)
• Documentation has been updated

[mergify]

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

• backport-7.x is the label to automatically backport to the 7.x branch.
• backport-7./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.

[apmmachine]

💚 Build Succeeded

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Build stats

• Start Time: 2022-03-15T01:11:33.787+0000

• Duration: 37 min 20 sec

Test stats 🧪

Test	Results
Failed	0
Passed	3911
Skipped	13
Total	3924

🤖 GitHub comments

To re-run your PR in the CI, just comment with:

• /test : Re-trigger the build.

• /hey-apm : Run the hey-apm benchmark.

• /package : Generate and publish the docker images.

• /test windows : Build & tests on Windows.

• run elasticsearch-ci/docs : Re-trigger the docs validation. (use unformatted text in the comment!)

[mergify]

This pull request is now in conflicts. Could you fix it @tobiasstadler? 🙏
To fixup this pull request, you can check out it locally. See documentation: https://help.github.com/articles/checking-out-pull-requests-locally/

git fetch upstream
git checkout -b fix-7387 upstream/fix-7387
git merge upstream/main
git push upstream fix-7387

[simitt]

/test

[marclop]

run elasticsearch-ci/docs

[simitt]

/test

[simitt]

/test

[axw]

LGTM, thank you!

[tobiasstadler]

Thank You!