fix RDDSuite

Author: witgo

core/src/test/scala/org/apache/spark/rdd/RDDSuite.scala

@@ -268,8 +268,9 @@ class RDDSuite extends FunSuite with SharedSparkContext {
 
     // we can optionally shuffle to keep the upstream parallel
     val coalesced5 = data.coalesce(1, shuffle = true)
-    assert(coalesced5.dependencies.head.rdd.dependencies.head.rdd.
-      asInstanceOf[ShuffledRDD[Int, Int, (Int, Int)]] !== null )
+    val isEquals = coalesced5.dependencies.head.rdd.dependencies.head.rdd.
+      asInstanceOf[ShuffledRDD[_, _, _]] != null
+    assert(isEquals)
 
     // when shuffling, we can increase the number of partitions
     val coalesced6 = data.coalesce(20, shuffle = true)