patch 8.2.3186: Vim9: not all failures for import tested

Problem:    Vim9: not all failures for import tested
Solution:   Test more import failures
diff --git a/src/errors.h b/src/errors.h
index 98a1098..af42428 100644
--- a/src/errors.h
+++ b/src/errors.h
@@ -511,7 +511,7 @@
 EXTERN char e_bool_required_for_argument_nr[]
 	INIT(= N_("E1212: Bool required for argument %d"));
 EXTERN char e_redefining_imported_item_str[]
-	INIT(= N_("E1213: Redefining imported item %s"));
+	INIT(= N_("E1213: Redefining imported item \"%s\""));
 #if defined(FEAT_DIGRAPHS) && defined(FEAT_EVAL)
 EXTERN char e_digraph_must_be_just_two_characters_str[]
 	INIT(= N_("E1214: Digraph must be just two characters: %s"));