Fix DynamicCheckpoint.create_ex() method doesn't pass size attr

[gsmj]

    @classmethod
    def create_ex(
        cls,
        x: float,
        y: float,
        z: float,
        size: float,
        stream_distance: float = StreamerTypes.CP_SD,
        worlds: Optional[list[int]] = None,
        interiors: Optional[list[int]] = None,
        players: Optional[list[int]] = None,
        areas: Optional[list[int]] = None,
        priority: int = 0,
    ) -> "DynamicCheckpoint":
        return cls(
            create_dynamic_cp_ex(
                x,
                y,
                z,  # size after z param
                stream_distance,
                worlds,
                interiors,
                players,
                areas,
                priority,
            )
        )