fix(src/emacs/lean-syntax.el): remove obsolete command set_opaque
fix(src/emacs/lean-syntax.el): remove obsolete command set_opaque

Signed-off-by: Leonardo de Moura <7610bae85f2b530654cc716772f1fe653373e892@microsoft.com>

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