Update MAINTAINER_GUIDE.md
Update MAINTAINER_GUIDE.md

sjakobi/stack,AndreasPK/stack,mrkkrp/stack,deech/stack,Fuuzetsu/stack,mrkkrp/stack,AndreasPK/stack,MichielDerhaeg/stack,sjakobi/stack,Heather/stack,martin-kolinek/stack,martin-kolinek/stack,anton-dessiatov/stack,AndrewRademacher/stack,MichielDerhaeg/stack,juhp/stack,AndrewRademacher/stack,Blaisorblade/stack,deech/stack,Fuuzetsu/stack,anton-dessiatov/stack,juhp/stack,Blaisorblade/stack,Heather/stack