[8.8](backport #35820) Fix panic when MaxRetryInterval is specified, but RetryInterval is not

[mergify]

This is an automatic backport of pull request #35820 done by Mergify.

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• Start Time: 2023-06-20T19:14:19.316+0000

• Duration: 84 min 55 sec

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Test	Results
Failed	0
Passed	26412
Skipped	1978
Total	28390

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