Couple small cleanups

Author: lutovich

driver/src/main/java/org/neo4j/driver/internal/handlers/PullAllResponseHandler.java

@@ -236,7 +236,7 @@ private Throwable extractFailure()
     {
         if ( failure == null )
         {
-            throw new IllegalStateException( "Can't consume failure because it does not exist" );
+            throw new IllegalStateException( "Can't extract failure because it does not exist" );
         }
 
         Throwable error = failure;

driver/src/main/java/org/neo4j/driver/internal/util/Futures.java

@@ -26,8 +26,6 @@
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Future;
 
-import static java.util.concurrent.CompletableFuture.completedFuture;
-
 public final class Futures
 {
     private Futures()
@@ -118,16 +116,4 @@ public static Throwable completionErrorCause( Throwable error )
         }
         return error;
     }
-
-    public static <T> CompletionStage<T> firstNotNull( CompletionStage<T> stage1, CompletionStage<T> stage2 )
-    {
-        return stage1.thenCompose( value ->
-        {
-            if ( value != null )
-            {
-                return completedFuture( value );
-            }
-            return stage2;
-        } );
-    }
 }

driver/src/test/java/org/neo4j/driver/v1/integration/TransactionAsyncIT.java

@@ -969,8 +969,6 @@ public void shouldFailToCommitWhenQueriesFailAndErrorNotConsumed() throws Interr
         tx.runAsync( "RETURN 10 / 0" );
         tx.runAsync( "CREATE (:TestNode)" );
 
-        Thread.sleep( 1000 );
-
         try
         {
             getBlocking( tx.commitAsync() );