Since FIXTURE_DIR_NAME is the name of the folder that contains the view
and tests modules of the webhook and another folder called "fixtures" that
store the fixtures, it is more appropriate to call it WEBHOOK_DIR_NAME,
especially when we want to refer to the view module using this variable.
Almost all webhook tests use this helper, except a few
webhooks that write to private streams.
Being concise is important here, and the name
`self.send_and_test_stream_message` always confused
me, since it sounds you're sending a stream message,
and it leaves out the webhook piece.
We should consider renaming `send_and_test_private_message`
to something like `check_webhook_private`, but I couldn't
decide on a great name, and it's very rarely used. So
for now I just made sure the docstrings of the two
sibling functions reference each other.
Generated by `pyupgrade --py3-plus --keep-percent-format` on all our
Python code except `zthumbor` and `zulip-ec2-configure-interfaces`,
followed by manual indentation fixes.
Signed-off-by: Anders Kaseorg <anders@zulipchat.com>