Revert "feat(core): Ensure that all actions are compared to fixed point in time (#1236) (#1458)" (#1471)

This reverts commit 51b8773528.

src/server/game/Mails/Mail.cpp

@@ -9,7 +9,6 @@
 #include "Log.h"
 #include "World.h"
 #include "ObjectMgr.h"
-#include "GameTime.h"
 #include "Player.h"
 #include "Unit.h"
 #include "BattlegroundMgr.h"
@@ -176,7 +175,7 @@ void MailDraft::SendMailTo(SQLTransaction& trans, MailReceiver const& receiver,
 
     uint32 mailId = sObjectMgr->GenerateMailID();
 
-    time_t deliver_time = GameTime::GetGameTime() + deliver_delay;
+    time_t deliver_time = time(NULL) + deliver_delay;
 
     //expire time if COD 3 days, if no COD 30 days, if auction sale pending 1 hour
     uint32 expire_delay;