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

Build failed. https://zuul.opendev.org/t/openstack/buildset/d9acadb10c9e4f8ca2f92d922f47a5... - openstack-tox-docs https://zuul.opendev.org/t/openstack/build/1c8bc97018524f75af35be8f0153abf0 : SUCCESS in 4m 33s - openstack-tox-py27 https://zuul.opendev.org/t/openstack/build/bbffe42688d94dc0b9adcdf2798da348 : SUCCESS in 6m 18s - openstack-tox-py36 https://zuul.opendev.org/t/openstack/build/0497acd6b5b74b0ba731e8f360d70584 : SUCCESS in 3m 54s - openstack-tox-py37 https://zuul.opendev.org/t/openstack/build/e8daff93c65740b1b05cdc2395be4672 : FAILURE in 4m 49s