Core/Scripts: set correct unit_flags on Scarlet Mine Car (#17844)

Closes #17816
(cherry picked from commit f3dc97f263cc14ba5a17d745b552586aecb36a59)

Rename 2016_08_24_08_world.sql to 2016_08_24_03_world.sql
(cherry picked from commit cabf6bd98a8f6c39c4173fb3f30a50708ad20093)

sql/updates/world/master/2017_02_18_15_world_2016_08_24_03_world.sql

@@ -0,0 +1,2 @@
+-- Scarlet Mine Car must have UNIT_FIELD_FLAGS UNIT_FLAG_IMMUNE_TO_PC
+UPDATE `creature_template` SET `unit_flags`= `unit_flags`| 520 WHERE `entry`= 28817;

src/server/scripts/EasternKingdoms/ScarletEnclave/chapter1.cpp

@@ -1022,7 +1022,6 @@ class npc_scarlet_miner_cart : public CreatureScript
         {
             npc_scarlet_miner_cartAI(Creature* creature) : PassiveAI(creature)
             {
-                me->SetFlag(UNIT_FIELD_FLAGS, UNIT_FLAG_IMMUNE_TO_PC);
                 me->SetDisplayId(me->GetCreatureTemplate()->Modelid1); // Modelid2 is a horse.
             }