Fixed position desync using Back Slide when being hit on pre-re

* Follow up to c4609b19d6

src/map/skill.cpp

@@ -8549,6 +8549,8 @@ int skill_castend_nodamage_id (struct block_list *src, struct block_list *bl, ui
 		clif_skill_nodamage(src, bl, skill_id, skill_lv, 1);
 #ifdef RENEWAL
 		clif_blown(src); // Always blow, otherwise it shows a casting animation. [Lemongrass]
+#else
+		clif_slide(bl, bl->x, bl->y); //Show the casting animation on pre-re
 #endif
 		break;