removed os.O_NONBLOCK from snippet

Author: rmliddle

tests/snippets/os_static.py

@@ -3,6 +3,5 @@
 assert os.O_RDONLY == 0
 assert os.O_WRONLY == 1
 assert os.O_RDWR == 2
-assert os.O_NONBLOCK == 4
 assert os.O_APPEND == 8
 assert os.O_CREAT == 512