Improve scripts for quests Breakfast Of Champions and A Bear of an Appetite (#17780)

Properly despawn the related GameObjects after use of the quest item, avoiding multiple use and summon

sql/updates/world/3.3.5/2016_99_99_99_world.sql

@@ -0,0 +1,5 @@
+DELETE FROM `spell_linked_spell` WHERE `spell_trigger`=66512;
+DELETE FROM `spell_script_names` WHERE `ScriptName` IN('spell_q14076_14092_pound_drum','spell_q12279_cast_net');
+INSERT INTO `spell_script_names` (`spell_id`,`ScriptName`) VALUES
+(66512,'spell_q14076_14092_pound_drum'),
+(48794,'spell_q12279_cast_net');