RIP: travisbot notifications
RIP: travisbot notifications

Summary:
This are noisy and don't provide real value, so remove
the webhooks.

Reviewed By: yns88

Differential Revision: D16115486

fbshipit-source-id: 1daa2d78f4e786a42dcc5779ccd30c36e02d2445

facebook/bistro,facebook/bistro,facebook/bistro,facebook/bistro,facebook/bistro,facebook/bistro