flake in IpVersions/AggregateIntegrationTest.PreviousPrioritiesRetryPredicate

[alyssawilk]

https://github.com/envoyproxy/envoy/actions/runs/13004331179/job/36268476922#step:17:2047

cc @ggreenway as the author in 2020, @bazmurphy as someone who is adding tests for the aggregate cluster and might be willing to take a look :-)