feat(frontends/lean/definition_cmds): add support for 'sorry'
feat(frontends/lean/definition_cmds): add support for 'sorry'

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