test: fix flaky debugModeExpiresBasedOnServerTime test #421

Job	Run time
test-platforms-and-versions (ubuntu-latest, 17)	3m 47s
test-platforms-and-versions (ubuntu-latest, 19)	3m 43s
test-platforms-and-versions (ubuntu-latest, 11)	3m 48s
test-platforms-and-versions (ubuntu-latest, 8)	3m 37s
test-packaging	4m 53s
test-contract-tests	4m 12s
	24m 0s

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