error msg fixed

src/main/java/org/redisson/RedissonKeys.java

@@ -289,7 +289,7 @@ public class RedissonKeys implements RKeys {
                 if (executed.decrementAndGet() == 0) {
                     if (failed.get() != null) {
                         if (count.get() > 0) {
-                            RedisException ex = new RedisException("" + count.get() + " keys deleted. But one or more nodes has an error", failed.get());
+                            RedisException ex = new RedisException("" + count.get() + " keys has been deleted. But one or more nodes has an error", failed.get());
                             result.setFailure(ex);
                         } else {
                             result.setFailure(failed.get());