Migrate testdata to new lambda syntax

compiler/testData/codegen/boxAgainstJava/sam/adapters/nonLiteralComparator.kt

@@ -4,7 +4,7 @@ fun box(): String {
     val list = ArrayList(Arrays.asList(3, 2, 4, 8, 1, 5))
     val expected = ArrayList(Arrays.asList(8, 5, 4, 3, 2, 1))
 
-    val f = { (a: Int, b: Int) -> b - a }
+    val f = { a: Int, b: Int -> b - a }
     JavaClass.sortIntList(list, f)
     return if (list == expected) "OK" else list.toString()
 }