Render 'annotation class not found' for error types in tests

After 13ae3d9 it became unclear whether an annotation mentioned in test data is
resolved or not, this change fixes that

compiler/testData/diagnostics/tests/annotations/AnnotationForObject.txt

@@ -1,6 +1,6 @@
 package
 
-@[ERROR : someErrorAnnotation]() public object Test {
+@[ERROR : someErrorAnnotation]() /* annotation class not found */ public object Test {
     private constructor Test()
     public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
     public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int