[8.0] Don't drop RUM unsampled transactions (backport #6669)

[mergify]

This is an automatic backport of pull request #6669 done by Mergify.

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• Start Time: 2021-11-22T11:33:07.654+0000

• Duration: 40 min 19 sec

• Commit: 5ee5191

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Test	Results
Failed	0
Passed	5622
Skipped	19
Total	5641

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