Register remote cluster compress setting (#35464)

This is a follow up to #35357. That commit failed to register the new
cluster.remote.cluster_name.transport.compress setting with
`ClusterSettings`. This commit fixes that.

server/src/main/java/org/elasticsearch/common/settings/ClusterSettings.java

@@ -294,6 +294,7 @@ public final class ClusterSettings extends AbstractScopedSettings {
                     RemoteClusterService.ENABLE_REMOTE_CLUSTERS,
                     RemoteClusterService.SEARCH_ENABLE_REMOTE_CLUSTERS,
                     RemoteClusterService.REMOTE_CLUSTER_PING_SCHEDULE,
+                    RemoteClusterService.REMOTE_CLUSTER_COMPRESS,
                     TransportService.TRACE_LOG_EXCLUDE_SETTING,
                     TransportService.TRACE_LOG_INCLUDE_SETTING,
                     TransportCloseIndexAction.CLUSTER_INDICES_CLOSE_ENABLE_SETTING,

server/src/test/java/org/elasticsearch/transport/RemoteClusterServiceTests.java

@@ -99,6 +99,7 @@ public class RemoteClusterServiceTests extends ESTestCase {
         assertTrue(ClusterSettings.BUILT_IN_CLUSTER_SETTINGS.contains(RemoteClusterService.REMOTE_INITIAL_CONNECTION_TIMEOUT_SETTING));
         assertTrue(ClusterSettings.BUILT_IN_CLUSTER_SETTINGS.contains(RemoteClusterService.REMOTE_NODE_ATTRIBUTE));
         assertTrue(ClusterSettings.BUILT_IN_CLUSTER_SETTINGS.contains(RemoteClusterService.REMOTE_CLUSTER_PING_SCHEDULE));
+        assertTrue(ClusterSettings.BUILT_IN_CLUSTER_SETTINGS.contains(RemoteClusterService.REMOTE_CLUSTER_COMPRESS));
     }
 
     public void testRemoteClusterSeedSetting() {