Fix travis-slack integration typo
Fix travis-slack integration typo

Summary: Fix a typo that caused no notifications to be posted.

Test Plan: Run `travis lint`, which did not complain about unknown section.

Reviewed By: sdwilsh

fbshipit-source-id: b6ac2d6

robbertvanginkel/buck,romanoid/buck,ilya-klyuchnikov/buck,brettwooldridge/buck,k21/buck,zpao/buck,kageiit/buck,shs96c/buck,Addepar/buck,JoelMarcey/buck,rmaz/buck,dsyang/buck,ilya-klyuchnikov/buck,marcinkwiatkowski/buck,Addepar/buck,JoelMarcey/buck,SeleniumHQ/buck,SeleniumHQ/buck,Addepar/buck,zhan-xiong/buck,JoelMarcey/buck,shybovycha/buck,marcinkwiatkowski/buck,SeleniumHQ/buck,rmaz/buck,shybovycha/buck,marcinkwiatkowski/buck,nguyentruongtho/buck,clonetwin26/buck,kageiit/buck,SeleniumHQ/buck,facebook/buck,zhan-xiong/buck,nguyentruongtho/buck,romanoid/buck,SeleniumHQ/buck,zhan-xiong/buck,zhan-xiong/buck,SeleniumHQ/buck,rmaz/buck,LegNeato/buck,SeleniumHQ/buck,marcinkwiatkowski/buck,clonetwin26/buck,shybovycha/buck,dsyang/buck,Addepar/buck,zpao/buck,JoelMarcey/buck,ilya-klyuchnikov/buck,ilya-klyuchnikov/buck,clonetwin26/buck,brettwooldridge/buck,robbertvanginkel/buck,clonetwin26/buck,romanoid/buck,marcinkwiatkowski/buck,romanoid/buck,robbertvanginkel/buck,zhan-xiong/buck,ilya-klyuchnikov/buck,k21/buck,LegNeato/buck,LegNeato/buck,marcinkwiatkowski/buck,LegNeato/buck,zpao/buck,marcinkwiatkowski/buck,nguyentruongtho/buck,shs96c/buck,zhan-xiong/buck,dsyang/buck,k21/buck,kageiit/buck,zpao/buck,robbertvanginkel/buck,marcinkwiatkowski/buck,zhan-xiong/buck,ilya-klyuchnikov/buck,marcinkwiatkowski/buck,rmaz/buck,marcinkwiatkowski/buck,shybovycha/buck,facebook/buck,LegNeato/buck,dsyang/buck,brettwooldridge/buck,shs96c/buck,SeleniumHQ/buck,JoelMarcey/buck,JoelMarcey/buck,marcinkwiatkowski/buck,kageiit/buck,rmaz/buck,shs96c/buck,k21/buck,facebook/buck,ilya-klyuchnikov/buck,dsyang/buck,SeleniumHQ/buck,zpao/buck,kageiit/buck,romanoid/buck,nguyentruongtho/buck,marcinkwiatkowski/buck,shybovycha/buck,nguyentruongtho/buck,brettwooldridge/buck,Addepar/buck,ilya-klyuchnikov/buck,Addepar/buck,k21/buck,k21/buck,dsyang/buck,clonetwin26/buck,shs96c/buck,shybovycha/buck,ilya-klyuchnikov/buck,Addepar/buck,ilya-klyuchnikov/buck,JoelMarcey/buck,k21/buck,brettwooldridge/buck,JoelMarcey/buck,brettwooldridge/buck,brettwooldridge/buck,shs96c/buck,k21/buck,dsyang/buck,rmaz/buck,k21/buck,rmaz/buck,clonetwin26/buck,dsyang/buck,kageiit/buck,romanoid/buck,robbertvanginkel/buck,shybovycha/buck,zhan-xiong/buck,nguyentruongtho/buck,dsyang/buck,JoelMarcey/buck,robbertvanginkel/buck,SeleniumHQ/buck,brettwooldridge/buck,rmaz/buck,robbertvanginkel/buck,LegNeato/buck,shybovycha/buck,dsyang/buck,SeleniumHQ/buck,romanoid/buck,romanoid/buck,brettwooldridge/buck,robbertvanginkel/buck,facebook/buck,shybovycha/buck,zpao/buck,Addepar/buck,zhan-xiong/buck,ilya-klyuchnikov/buck,LegNeato/buck,shybovycha/buck,brettwooldridge/buck,JoelMarcey/buck,brettwooldridge/buck,robbertvanginkel/buck,Addepar/buck,SeleniumHQ/buck,LegNeato/buck,rmaz/buck,JoelMarcey/buck,rmaz/buck,k21/buck,SeleniumHQ/buck,Addepar/buck,shybovycha/buck,k21/buck,Addepar/buck,dsyang/buck,facebook/buck,clonetwin26/buck,shybovycha/buck,shs96c/buck,shs96c/buck,robbertvanginkel/buck,clonetwin26/buck,brettwooldridge/buck,clonetwin26/buck,k21/buck,romanoid/buck,LegNeato/buck,clonetwin26/buck,ilya-klyuchnikov/buck,dsyang/buck,romanoid/buck,zhan-xiong/buck,facebook/buck,robbertvanginkel/buck,clonetwin26/buck,brettwooldridge/buck,clonetwin26/buck,ilya-klyuchnikov/buck,Addepar/buck,LegNeato/buck,zhan-xiong/buck,dsyang/buck,shs96c/buck,rmaz/buck,shs96c/buck,facebook/buck,LegNeato/buck,robbertvanginkel/buck,JoelMarcey/buck,zhan-xiong/buck,zpao/buck,shybovycha/buck,Addepar/buck,robbertvanginkel/buck,clonetwin26/buck,marcinkwiatkowski/buck,shs96c/buck,LegNeato/buck,rmaz/buck,romanoid/buck,nguyentruongtho/buck,zhan-xiong/buck,romanoid/buck,shs96c/buck,shs96c/buck,JoelMarcey/buck,romanoid/buck,rmaz/buck,LegNeato/buck,kageiit/buck,k21/buck