Part of #9744
Removes all redundant `# -*- coding: utf-8 -*-` lines from files, as python 3 automatically reads source code as utf-8 now.
`Signed-off-by: Jonathan de Jong <jonathan@automatia.nl>`
The two are equivalent, but really we want to check the HTTP result that got
returned to the channel, not the code that the Request object *intended* to
return to the channel.
Where we want to render a request against a specific Resource, call the global
make_request() function rather than the one in HomeserverTestCase, allowing us
to pass in an appropriate `Site`.
