Corrected SQL upgrade format

* Fixed incorrect ticks.
Thanks to @Haikenz!

sql-files/upgrades/upgrade_20180830.sql

@@ -1,3 +1,3 @@
-UPDATE `char` ch, `skill` sk SET ch.`skill_point` = ch.`skill_point + sk.`lv` WHERE sk.`id` = 2049 AND ch.`char_id` = sk.`char_id`;
+UPDATE `char` SET `char`.`skill_point` = `char`.`skill_point` + `skill`.`lv` WHERE `skill`.`id` = 2049 AND `char`.`char_id` = `skill`.`char_id`;
 
 DELETE FROM `skill` WHERE `id` = 2049;