stack-build/Dockerfile: remove couple of "fixme" comments
stack-build/Dockerfile: remove couple of "fixme" comments

mrkkrp/stack,Fuuzetsu/stack,MichielDerhaeg/stack,mrkkrp/stack,anton-dessiatov/stack,martin-kolinek/stack,juhp/stack,AndreasPK/stack,AndreasPK/stack,martin-kolinek/stack,MichielDerhaeg/stack,Fuuzetsu/stack,juhp/stack,anton-dessiatov/stack