chore(tests/library/blast/union_find): fix style
chore(tests/library/blast/union_find): fix style

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