[wsgi] Drop calls to repo.start_looping_tasks It's unlikely that these implementations were ever used so we do not bother with deprecation or a warning. We just drop the call to this method which should not be called from within a WSGI application. Related to #17057223.

Twisted < 16.0.0
requests
webtest
cubicweb-blog
cubicweb-file
cubicweb-tag