Investigate PatroniRegistryServiceDnsLookupsApdexSLOViolation

Related to the PatroniRegistryServiceDnsLookupsApdexSLOViolation alert that we've been seeing more frequently on .com (sample).

This alert was introduced recently and the tolerated/satisfied thresholds for production have been defined based on the metrics we observed in staging (source), so it's possible we need to adjust them to take into account the production workload. Something we know is that it's technically possible for registry pods to come up before consul is ready to serve connections and therefore we might be experiencing a decent amount of these during scale up events, which we don't see that much in staging.