feat(shell/lean): use locking also for the index file
feat(shell/lean): use locking also for the index file

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