GHSA-hr73-3gpv-hh6q: Steeltoe.Discovery.Eureka: malformed enum/bool/timestamp field aborts entire registry fetch (DoS)

## Summary Steeltoe's Eureka discovery client deserializes the registry response as a single unit. If any registered instance contains a field value that cannot be parsed (for example, an unrecognized `actionType`, a non-boolean value for `isCoordinatingDiscoveryServer`, or a non-numeric timestamp), deserialization of the entire registry fails. All Steeltoe Eureka clients connected to that registry then receive an empty or stale instance list until the malformed registration is removed. …