Fixed: chroot-installation_stretch_install_haskell_upgrade_to_sid/191

[jenkins at jenkins.debian.net]

See https://jenkins.debian.net/job/chroot-installation_stretch_install_haskell_upgrade_to_sid/191//console or just https://jenkins.debian.net/job/chroot-installation_stretch_install_haskell_upgrade_to_sid/191/ for more information.