Append newline to EOF for .txt test data files

Reverts and fixes 102f0d3

compiler/testData/diagnostics/tests/imports/ImportResolutionOrder.txt

@@ -26,4 +26,4 @@ package d {
         public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
         public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
     }
-}
+}

compiler/testData/diagnostics/tests/imports/ImportsHiddenByDefinitionInTheSameFile.txt

@@ -5,4 +5,4 @@ internal final class List {
     public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
     public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
     public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
-}
+}

compiler/testData/diagnostics/tests/imports/RenameOnImport.txt

@@ -6,4 +6,4 @@ package a {
 
 package b {
     internal val y: kotlin.Int = 1
-}
+}