Fix WritePlanNodeSplitTest compilation

Author: Caideyipi

iotdb-core/datanode/src/test/java/org/apache/iotdb/db/queryengine/plan/planner/node/write/WritePlanNodeSplitTest.java

@@ -56,6 +56,7 @@
 
 import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;