fix(.travis.yml): typo
fix(.travis.yml): typo

Signed-off-by: Leonardo de Moura <7610bae85f2b530654cc716772f1fe653373e892@microsoft.com>

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