[test] don't call optimize while shard is relocating

In this test we assume that after waitForRelocation() has returned shards
are no more relocated and optimize will therefore succeed always.
However, because the test does not wait for green status, relocations can
still start after waitForRelocation() has returned successfully.

see #13266 for a detailed explanation

core/src/test/java/org/elasticsearch/search/query/SearchQueryIT.java

@@ -143,7 +143,7 @@ public class SearchQueryIT extends ESIntegTestCase {
         client().prepareIndex("test", "type1", "1").setSource("field1", "value1").get();
         client().prepareIndex("test", "type1", "2").setSource("field1", "value2").get();
         client().prepareIndex("test", "type1", "3").setSource("field1", "value3").get();
-
+        ensureGreen();
         waitForRelocation();
         optimize();
         refresh();