tests: set umask explicitly
tests: set umask explicitly

The umask is typically 022, but in some environments it's not.

nodakai/watchman,wez/watchman,wez/watchman,wez/watchman,facebook/watchman,facebook/watchman,facebook/watchman,dhruvsinghal/watchman,facebook/watchman,nodakai/watchman,dhruvsinghal/watchman,kwlzn/watchman,dhruvsinghal/watchman,facebook/watchman,kwlzn/watchman,facebook/watchman,facebook/watchman,wez/watchman,wez/watchman,facebook/watchman,kwlzn/watchman,dhruvsinghal/watchman,nodakai/watchman,kwlzn/watchman,nodakai/watchman,dhruvsinghal/watchman,nodakai/watchman,wez/watchman,kwlzn/watchman,facebook/watchman,wez/watchman,wez/watchman,kwlzn/watchman,nodakai/watchman,kwlzn/watchman,nodakai/watchman,nodakai/watchman,wez/watchman,dhruvsinghal/watchman,nodakai/watchman,dhruvsinghal/watchman,dhruvsinghal/watchman