Comment 2 for bug 1832367

Actually I guess that plugin registry doc builder is OK since there are redirects:

osboxes@osboxes:~/git/watcher$ python3
Python 3.6.7 (default, Oct 22 2018, 11:32:17)
[GCC 8.2.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import urllib.request as urllib
>>> urllib.urlopen("https://git.openstack.org/cgit/watcher/plain/devstack/upgrade/upgrade.sh").code
200
>>> quit()

https://docs.openstack.org/grenade/latest/plugin-registry.html