[8.0] systemtest: Skip TestTailSampling for now (backport #7015)

[mergify]

This is an automatic backport of pull request #7015 done by Mergify.

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• Start Time: 2022-01-10T09:35:02.370+0000

• Duration: 40 min 48 sec

• Commit: 6c1136e

Test stats 🧪

Test	Results
Failed	0
Passed	5624
Skipped	20
Total	5644

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