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

Build failed. https://zuul.opendev.org/t/openstack/buildset/68321baf9a2b4db797634dbbfaaeac... - openstack-tox-docs https://zuul.opendev.org/t/openstack/build/83cc046dfc2c4530adc5e5d7e14b93de : SUCCESS in 3m 59s - openstack-tox-py27 https://zuul.opendev.org/t/openstack/build/8219fb9a364b4d4690142d3c4308eb2c : SUCCESS in 4m 47s - openstack-tox-py36 https://zuul.opendev.org/t/openstack/build/a16938cdc5fb4ee590c8da6128a619a7 : SUCCESS in 4m 33s - openstack-tox-py37 https://zuul.opendev.org/t/openstack/build/a41f0717afc24742879ff7fa96c24dfb : FAILURE in 4m 31s