Some tests use the `client` fixture but don’t call any of its methods.
The reason for doing this is because the test depends on something in
the request context.
This commit replaces all those instances with `client_request`, which
also sets the request context.
These tests are the last ones that still use the `client` fixture. By
replacing it with `client_request` we will be able to say that no tests
should be using the `client` fixture directly.
Previously some of the tests for code in the "formatters" module
were in tests for the "utils" module. This moves them to where
they should be. While two of these methods are probably more utils
than formatters, I'd like to postpone a refactor of that module
for now, and focus on slimming down test for utils/__init__.py.
