patch 8.2.2266: Vim9: it can be hard to see where white space is missing

Problem:    Vim9: it can be hard to see where white space is missing.
Solution:   Mention the text where the error was seen. (closes #7580)
diff --git a/src/errors.h b/src/errors.h
index 6f4ac0e..eb7239b 100644
--- a/src/errors.h
+++ b/src/errors.h
@@ -41,8 +41,8 @@
 	INIT(= N_("E1002: Syntax error at %s"));
 EXTERN char e_missing_return_value[]
 	INIT(= N_("E1003: Missing return value"));
-EXTERN char e_white_space_required_before_and_after_str[]
-	INIT(= N_("E1004: White space required before and after '%s'"));
+EXTERN char e_white_space_required_before_and_after_str_at_str[]
+	INIT(= N_("E1004: White space required before and after '%s' at \"%s\""));
 EXTERN char e_too_many_argument_types[]
 	INIT(= N_("E1005: Too many argument types"));
 EXTERN char e_str_is_used_as_argument[]