[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.
[server] Drop inexistent "bootstrap" argument in Repository initialization
This is a missing bit from 5de78b6fff2e. Unfortunately this code appears to be
uncovered by our test suite.