Attempt at fixing publish step (#2898)
Attempt at fixing publish step (#2898)

Summary:
Uses a custom GITHUB_PUBLISH_TOKEN with push permissions instead of the default provided GITHUB_TOKEN that cannot push to protected branches.
Pull Request resolved: https://github.com/facebook/relay/pull/2898

Test Plan: Let's see if this fixes the publish...

Differential Revision: D18072386

fbshipit-source-id: dc9eea784977dbc1c00922e6f000e467b9b02e21

iamchenxin/relay,voideanvalue/relay,facebook/relay,atxwebs/relay,voideanvalue/relay,cpojer/relay,cpojer/relay,kassens/relay,yungsters/relay,facebook/relay,xuorig/relay,xuorig/relay,iamchenxin/relay,cpojer/relay,josephsavona/relay,josephsavona/relay,xuorig/relay,atxwebs/relay,yungsters/relay,wincent/relay,iamchenxin/relay,yungsters/relay,kassens/relay,kassens/relay,xuorig/relay,voideanvalue/relay,wincent/relay,wincent/relay,wincent/relay,voideanvalue/relay,wincent/relay,josephsavona/relay,iamchenxin/relay,xuorig/relay,atxwebs/relay,wincent/relay,facebook/relay,kassens/relay,kassens/relay,voideanvalue/relay,xuorig/relay,cpojer/relay,facebook/relay,atxwebs/relay,kassens/relay,voideanvalue/relay,facebook/relay,facebook/relay