Fix flaky xds Translator TestRunner

*Description*:
Fix and re enable flaky Xds [TestRunner](https://github.com/envoyproxy/gateway/blob/5bf94c11e16a5c6bda2938de70feb15d2b60e626/internal/xds/translator/runner/runner_test.go#L16) 

[optional *Relevant Links*:]
Intermittent failures seen in https://github.com/envoyproxy/gateway/actions/runs/3184962312/jobs/5193973518#step:4:110
