Scripts/Quests: Fix Red Snapper - Very Tasty! GOb

Fix 'School of Red Snapper' now disappear correctly when using 'Draenei Fishing Net', the bug is caused because the GameObject is SpellFocus type.

Fix: #1673
I tried with ConditionScript, but ***sourceInfo.mConditionTargets[condition->ConditionTarget]*** is TypeId Player and not is valid.
```sql
DELETE FROM `conditions` WHERE `SourceTypeOrReferenceId`=17 AND `SourceEntry`=29866 AND `ConditionTypeOrReference`=31 AND `ConditionValue1`=5 AND `ConditionValue2`=181616;
INSERT INTO `conditions` (`SourceTypeOrReferenceId`, `SourceGroup`, `SourceEntry`, `SourceId`, `ElseGroup`, `ConditionTypeOrReference`, `ConditionTarget`, `ConditionValue1`, `ConditionValue2`, `ConditionValue3`, `NegativeCondition`, `ErrorType`, `ErrorTextId`, `ScriptName`, `Comment`) VALUES
(17, 0, 29866, 0, 0, 31, 0, 5, 181616, 0, 0, 102, 0, 'condition_q9452_cast_net', NULL);
```