feat(Core/Misc): change how Position struct is retrieved (#9017)

Update Position::GetPosition() and similar methods signatures to reflect 2a4c9bc changes by return a Position object instead of accepting a Position parameter by reference.

Cherry pick of 2585e799f9

src/server/game/Entities/Player/Player.cpp

@@ -1439,8 +1439,7 @@ bool Player::TeleportTo(uint32 mapid, float x, float y, float z, float orientati
         // near teleport, triggering send MSG_MOVE_TELEPORT_ACK from client at landing
         if (!GetSession()->PlayerLogout())
         {
-            Position oldPos;
-            GetPosition(&oldPos);
+            Position oldPos = GetPosition();
             Relocate(x, y, z, orientation);
             SendTeleportAckPacket();
             SendTeleportPacket(oldPos); // this automatically relocates to oldPos in order to broadcast the packet in the right place