Fix typo in .travis.yml
Fix typo in .travis.yml

soonhokong/lean,Kha/lean,soonhokong/lean-osx,leanprover-community/lean,dselsam/lean,javra/lean,rlewis1988/lean,soonhokong/lean,rlewis1988/lean,fgdorais/lean,avigad/lean,fpvandoorn/lean2,leanprover/lean,Kha/lean,javra/lean,levnach/lean,leanprover-community/lean,leanprover-community/lean,eigengrau/lean,eigengrau/lean,fpvandoorn/lean,htzh/lean,c-cube/lean,fpvandoorn/lean,johoelzl/lean,codyroux/lean0.1,UlrikBuchholtz/lean,leanprover-community/lean,eigengrau/lean,fgdorais/lean,soonhokong/lean-windows,dselsam/lean,avigad/lean,leodemoura/lean,soonhokong/lean-windows,avigad/lean,soonhokong/lean,UlrikBuchholtz/lean,soonhokong/lean-osx,digama0/lean,levnach/lean,leodemoura/lean,soonhokong/lean-osx,dselsam/lean,levnach/lean,eigengrau/lean,soonhokong/lean-osx,digama0/lean,javra/lean,digama0/lean,leodemoura/lean,soonhokong/lean,codyroux/lean0.1,sp3ctum/lean,dselsam/lean,digama0/lean,rlewis1988/lean,leanprover/lean,avigad/lean,digama0/lean,fpvandoorn/lean2,leanprover-community/lean,johoelzl/lean,johoelzl/lean,htzh/lean,fgdorais/lean,leodemoura/lean,fgdorais/lean,digama0/lean,fpvandoorn/lean,dselsam/lean,rlewis1988/lean,johoelzl/lean,sp3ctum/lean,leodemoura/lean,javra/lean,soonhokong/travis_test,soonhokong/lean-osx,soonhokong/travis_test,avigad/lean,leanprover/lean,fpvandoorn/lean2,soonhokong/lean-windows,johoelzl/lean,codyroux/lean0.1,c-cube/lean,c-cube/lean,UlrikBuchholtz/lean,levnach/lean,codyroux/lean0.1,UlrikBuchholtz/lean,c-cube/lean,sp3ctum/lean,rlewis1988/lean,fgdorais/lean,javra/lean,levnach/lean,leanprover-community/lean,htzh/lean,soonhokong/lean-windows,sp3ctum/lean,sp3ctum/lean,Kha/lean,fpvandoorn/lean,fgdorais/lean,soonhokong/lean,leanprover/lean,avigad/lean,htzh/lean,leanprover/lean,Kha/lean,soonhokong/lean-windows,leanprover/lean,htzh/lean,Kha/lean,fpvandoorn/lean2,johoelzl/lean,fpvandoorn/lean2,c-cube/lean,soonhokong/travis_test,soonhokong/travis_test,rlewis1988/lean,eigengrau/lean,UlrikBuchholtz/lean,leodemoura/lean,fpvandoorn/lean,fpvandoorn/lean,dselsam/lean,Kha/lean