This follows a correction made in twisted/twisted#1664 and should fix our Twisted Trial CI job.
Until that change is in a twisted release, we'll have to ignore the type
of the `host` argument. I've raised #10899 to remind us to review the
issue in a few months' time.
Adds missing type hints to methods in the synapse.handlers
module and requires all methods to have type hints there.
This also removes the unused construct_auth_difference method
from the FederationHandler.
Turns out that the functionality added in #10546 to skip TLS was incompatible
with older Twisted versions, so we need to be a bit more inventive.
Also, add a test to (hopefully) not break this in future. Sadly, testing TLS is
really hard.
