fix typo in Guides-Mutations
fix typo in Guides-Mutations

Summary:
I thought it should be `An array` rather than `Any array`
Closes https://github.com/facebook/relay/pull/1143

Reviewed By: steveluscher

Differential Revision: D3304359

Pulled By: kassens

fbshipit-source-id: 6ea299e08955eefe5a53cd63359fdfb529620514

voideanvalue/relay,yungsters/relay,cpojer/relay,voideanvalue/relay,xuorig/relay,atxwebs/relay,facebook/relay,iamchenxin/relay,xuorig/relay,chentsulin/relay,zpao/relay,kassens/relay,apalm/relay,rosskevin/relay,facebook/relay,kassens/relay,voideanvalue/relay,gabelevi/relay,freiksenet/relay,kassens/relay,freiksenet/relay,gabelevi/relay,benjaminogles/relay,gabelevi/relay,chirag04/relay,atxwebs/relay,xuorig/relay,apalm/relay,voideanvalue/relay,zpao/relay,kassens/relay,iamchenxin/relay,rosskevin/relay,voideanvalue/relay,facebook/relay,josephsavona/relay,chentsulin/relay,apalm/relay,benjaminogles/relay,chirag04/relay,xuorig/relay,chirag04/relay,wincent/relay,dbslone/relay,chentsulin/relay,dbslone/relay,facebook/relay,iamchenxin/relay,zpao/relay,atxwebs/relay,wincent/relay,xuorig/relay,kassens/relay,josephsavona/relay,josephsavona/relay,atxwebs/relay,cpojer/relay,wincent/relay,wincent/relay,facebook/relay,wincent/relay,freiksenet/relay,cpojer/relay,kassens/relay,yungsters/relay,cpojer/relay,benjaminogles/relay,facebook/relay,xuorig/relay,wincent/relay,voideanvalue/relay,iamchenxin/relay,yungsters/relay