DB - Areatrigger - Removes warnings when booting the server (#819)

* DB - Areatrigger - Removes warnings when booting the server

There are 3 triggers that are from the areatrigger.dbc which are useless since the linked maps don't exist.
It's probably a mistake from blizz.

* Wrong database chosen...

data/sql/updates/pending_db_world/rev_1522263653566045620.sql

@@ -0,0 +1,3 @@
+INSERT INTO version_db_world(sql_rev) VALUES ('1522263653566045620');
+
+DELETE FROM `areatrigger` WHERE map IN (24,28);