[Openstack-stable-maint] Stable check of openstack/horizon for ref refs/heads/stable/train failed

Build failed. - openstack-tox-docs https://zuul.opendev.org/t/openstack/build/554224d540724735857a30a538bd30c3 : SUCCESS in 8m 36s - openstack-tox-py27 https://zuul.opendev.org/t/openstack/build/ee9c3a0baa7448068f7621bb34524f90 : SUCCESS in 12m 47s - openstack-tox-py36 https://zuul.opendev.org/t/openstack/build/9963d4864f0f4bdcac816e0c251d4767 : SUCCESS in 11m 05s - openstack-tox-py37 https://zuul.opendev.org/t/openstack/build/be3774eba229454bbdd22d2b2018527d : FAILURE in 4m 57s