patch 9.0.2055: Vim9: non-consistent error messages

Problem:  Vim9: non-consistent error messages
Solution: make error messages more consistent with common structure

Adjust vim9class messages to follow common pattern.
[Variable|Method] "var-or-meth-name" ... class "class-name"

closes: #13391

Signed-off-by: Christian Brabandt <cb@256bit.org>
Co-authored-by: Ernie Rael <errael@raelity.com>
diff --git a/src/errors.h b/src/errors.h
index 7b1181a..79a785e 100644
--- a/src/errors.h
+++ b/src/errors.h
@@ -3396,9 +3396,9 @@
 EXTERN char e_using_object_as_string[]
 	INIT(= N_("E1324: Using an object as a String"));
 EXTERN char e_method_not_found_on_class_str_str[]
-	INIT(= N_("E1325: Method not found on class \"%s\": %s"));
+	INIT(= N_("E1325: Method \"%s\" not found in class \"%s\""));
 EXTERN char e_variable_not_found_on_object_str_str[]
-	INIT(= N_("E1326: Variable not found on object \"%s\": %s"));
+	INIT(= N_("E1326: Variable \"%s\" not found in object \"%s\""));
 EXTERN char e_object_required_found_str[]
 	INIT(= N_("E1327: Object required, found %s"));
 EXTERN char e_constructor_default_value_must_be_vnone_str[]