Update to github.com/docker/distribution 2.8.1

[andrewkroh]

The checksum of 2.8.0 was invalid causing security warnings.

[ph]

/test

[mergify]

This pull request does not have a backport label. Could you fix it @andrewkroh? 🙏
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 8./d branch. /d is the digit

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

[ph]

Thanks @andrewkroh

[elasticmachine]

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• Start Time: 2022-03-10T20:29:04.551+0000

• Duration: 17 min 42 sec

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[ph]

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