PHILADELPHIA — Egor Zamula has skated outdoors in the cold before and he likes it. The Flyers defenseman played on an outdoor rink in Regina, Saskatchewan, with the Calgary Hitmen of the Western Hockey League in the 2019 Prairie Classic. But the 21 degrees that day was balmy compared with what he experienced growing up in Russia. When he was a kid in Chelyabinsk, boards would be put up in front of his apartment building and water would be laid down. It didn’t take long for it to be playable — the temperature was around 31 below zero. “I think it’s a good experience to play an outdoor game. ……