safer start

Author: original-brownbear

server/src/test/java/org/elasticsearch/action/search/MockSearchPhaseContext.java

@@ -31,7 +31,6 @@
 import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
-import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicReference;
 import java.util.function.Supplier;