Fixed an invalid primary key in web.sql (#7304)

Fixes #7290

Thanks to @Tolimatoi

sql-files/upgrades/upgrade_20221001.sql

@@ -0,0 +1,4 @@
+ALTER TABLE `merchant_configs`
+	DROP PRIMARY KEY,
+	ADD PRIMARY KEY (`world_name`, `account_id`, `char_id`, `store_type`)
+;

sql-files/web.sql

@@ -46,5 +46,5 @@ CREATE TABLE IF NOT EXISTS `merchant_configs` (
   `char_id` INT(11) UNSIGNED NOT NULL,
   `store_type` tinyint(3) UNSIGNED NOT NULL DEFAULT 0,
   `data` longtext NOT NULL,
-  PRIMARY KEY (`world_name`, `account_id`, `char_id`)
+  PRIMARY KEY (`world_name`, `account_id`, `char_id`, `store_type`)
 ) ENGINE=MyISAM;