I also ran into this error on a dockerized Plone 5.0.8 site, after rebuilding the image, that was supposed to be bullet proof..
Jens gave the right hint, it depends on zope.interface, especially if you use 'zope.interface =' in versions section of your buildout.cfg
In this case Plone gets a more recent version of zope.interface (4.7.1 instead of) and it will break the site.
Solution: Avoid using 'zope.interface =' or pin it to the correct version.