Revert "Breaking change for 8.0, namespace_annotations replaced by na…

[MichaelKatsoulis]

…mespace.annotations (#28230)"

This reverts commit 058c405.

[botelastic]

This pull request doesn't have a Team:<team> label.

[mergify]

This pull request does not have a backport label. Could you fix it @MichaelKatsoulis? 🙏
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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• Start Time: 2021-11-22T14:41:05.819+0000

• Duration: 91 min 4 sec

• Commit: 2b2d507

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Test	Results
Failed	0
Passed	7128
Skipped	16
Total	7144

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