Fix thread races in SSL tests
Fix thread races in SSL tests

celluloid/nio4r,frsyuki/nio4r,marshall-lee/nio4r,celluloid/nio4r,marshall-lee/nio4r,tpetchel/nio4r,marshall-lee/nio4r,tpetchel/nio4r,frsyuki/nio4r,tpetchel/nio4r,celluloid/nio4r,frsyuki/nio4r