chore(library/definitional/equations): fix style
chore(library/definitional/equations): fix style

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