Fix tests

Author: alexey-ivanov-es

server/src/main/java/org/elasticsearch/cluster/metadata/ProjectMetadata.java

@@ -2182,10 +2182,16 @@ public Iterator<? extends ToXContent> toXContentChunked(ToXContent.Params p) {
             ),
             indices,
             customs,
+            multiProject ?
+                Iterators.single((builder, params) -> {
+                    builder.startObject("settings");
+                    settings.toXContent(builder, new ToXContent.MapParams(Collections.singletonMap("flat_settings", "true")));
+                    return builder.endObject();
+                })
+                : Collections.emptyIterator(),
             multiProject
                 ? ChunkedToXContentHelper.object("reserved_state", reservedStateMetadata().values().iterator())
-                : Collections.emptyIterator(),
-            multiProject ? ChunkedToXContentHelper.object("settings", Iterators.single(settings)) : Collections.emptyIterator()
+                : Collections.emptyIterator()
         );
     }
 

server/src/test/java/org/elasticsearch/cluster/ClusterStateTests.java

@@ -499,6 +499,7 @@ public void testToXContentWithMultipleProjects() throws IOException {
                           }
                         },
                         "index-graveyard": { "tombstones": [] },
+                        "settings": {},
                         "reserved_state": {}
                       },
                       {
@@ -557,13 +558,15 @@ public void testToXContentWithMultipleProjects() throws IOException {
                           }
                         },
                         "index-graveyard": { "tombstones": [] },
+                        "settings": {},
                         "reserved_state": {}
                       },
                       {
                         "id": "WHyuJ0uqBYOPgHX9kYUXlZ",
                         "templates": {},
                         "indices": {},
                         "index-graveyard": { "tombstones": [] },
+                        "settings": {},
                         "reserved_state": {}
                       }
                     ],