Append newline to EOF for .txt test data files

Reverts and fixes 102f0d3

compiler/testData/loadJava/compiledKotlin/visibility/PrivateClassMembers.txt

@@ -10,4 +10,4 @@ public final class PrivateClassMembers {
     private final val v: kotlin.Int = 0
         private final fun <get-v>(): kotlin.Int
     private final fun f(): kotlin.Int
-}
+}