The German capital is expanding a temporary refugee shelter at its former airport, Tegel, to accommodate 3,600 Ukrainians. Berlin has been struggling to host civilians who have recently fled Russian attacks on vital infrastructure ahead of the upcoming cold winter months. While two former terminals at Tegel Airport were already opened for Ukrainian refugees in the spring, Berlin’s state government is now racing to outfit two big tents on the tarmac with heaters ahead of the winter. It has also opened a third terminal for registration of further arrivals and put up 900 new beds, officials said …