[7.x](backport #28548) [Heartbeat] Make run_once syntax a boolean

[mergify]

This is an automatic backport of pull request #28548 done by Mergify.

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• Start Time: 2021-10-20T00:36:23.981+0000

• Duration: 82 min 18 sec

• Commit: 991ddb3

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Test	Results
Failed	0
Passed	3556
Skipped	80
Total	3636

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