feat(library/blast/congruence_closure): use blast.cc.heq by default
feat(library/blast/congruence_closure): use blast.cc.heq by default

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