Append newline to EOF for .txt test data files

Reverts and fixes 102f0d3

compiler/testData/diagnostics/tests/library/Collections.txt

@@ -10,4 +10,4 @@ package collections {
     internal fun </*0*/ K, /*1*/ V> testMutableMap(/*0*/ m: kotlin.MutableMap<K, V>): kotlin.Unit
     internal fun </*0*/ T> testMutableSet(/*0*/ s: kotlin.MutableSet<T>, /*1*/ t: T): kotlin.Unit
     internal fun </*0*/ T> testSet(/*0*/ s: kotlin.Set<T>, /*1*/ t: T): kotlin.Unit
-}
+}

compiler/testData/diagnostics/tests/library/kt828.txt

@@ -1,3 +1,3 @@
 package
 
-internal fun test(): kotlin.Unit
+internal fun test(): kotlin.Unit