mononoke/opensource: temporarily remove mononoke manifest
mononoke/opensource: temporarily remove mononoke manifest

Summary: The oss jobs are causing problems to the developers now, lets disable them temporarily.

Reviewed By: StanislavGlebik

Differential Revision: D21400898

fbshipit-source-id: f7a3567056633d9eef98a8d05a37cd029c9e506c

facebook/watchman,nodakai/watchman,facebook/watchman,nodakai/watchman,nodakai/watchman,nodakai/watchman,facebook/watchman,nodakai/watchman,facebook/watchman,facebook/watchman,facebook/watchman,nodakai/watchman,facebook/watchman,nodakai/watchman,nodakai/watchman,facebook/watchman,nodakai/watchman,facebook/watchman