Core/Scripts: fix non-functional Celestial Planetarium Access GO

- Client only sends CMSG_GAMEOBJ_REPORT_USE for this one

Closes #19982

(cherry picked from commit b490d3f5ad)

src/server/scripts/Northrend/Ulduar/Ulduar/boss_algalon_the_observer.cpp

@@ -990,7 +990,7 @@ class go_celestial_planetarium_access : public GameObjectScript
 
             InstanceScript* instance;
 
-            bool GossipHello(Player* player) override
+            bool OnReportUse(Player* player) override
             {
                 if (me->HasFlag(GO_FLAG_IN_USE))
                     return true;