Service Discovery DiscoverInstances operation doesn't work due to hostPrefix being defined

Dependencies

{:deps {com.cognitect.aws/api       {:mvn/version "0.8.505"}
        com.cognitect.aws/endpoints {:mvn/version "1.1.11.960"}
        com.cognitect.aws/servicediscovery       {:mvn/version "809.2.784.0"}}}

Description with failing test case

While using clj REPL I invoked the DiscoverInstances operation resulting in an UnknownOperationException.

(require '[cognitect.aws.client.api :as aws])
...
(aws/invoke sd {:op :DiscoverInstances
                :request {:NamespaceName "green.int.auto.sd"
                          :ServiceName "MyService"}})
=> {:__type "UnknownOperationException", :cognitect.anomalies/category :cognitect.anomalies/incorrect}

I noted that the service discovery operation is unique in that it has the following:

:endpoint {:hostPrefix "data-"}

as part of the operation definition:

:DiscoverInstances {:name "DiscoverInstances",
                                  :http {:method "POST",
                                         :requestUri "/"},
                                  :input {:shape "DiscoverInstancesRequest"},
                                  :output {:shape "DiscoverInstancesResponse"},
                                  :errors [{:shape "ServiceNotFound"}
                                           {:shape "NamespaceNotFound"}
                                           {:shape "InvalidInput"}
                                           {:shape "RequestLimitExceeded"}],
                                  :endpoint {:hostPrefix "data-"}}

When using a client that has the following added at creation time:

:endpoint-override {:hostname "data-servicediscovery.ap-southeast-2.amazonaws.com"}

so as to include the 'data-' prefix to the normal service discovery endpoint, executing the DiscoverInstances operation is successful.

Reproduce the DiscoverInstances call with the dependency versions and request shown, then inspect how the operation's hostPrefix is handled when constructing the endpoint. Compare the failing default client with the endpoint-override case. Done means DiscoverInstances succeeds without manually adding the data- prefix, with coverage for this operation.