This PR aims to close#14253
We keep the default behavior using the Coder logo if there's no logo
set.
Otherwise we want to use the logo based on the URL set in appearance.
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Co-authored-by: defelmnq <yvincent@coder.com>
A bunch of notification tests create a whole `coderd`, when all they use is the database and logger. This makes the tests more expensive to run, and pollutes the test logs with a bunch of stuff that doesn't matter (e.g. tailnet).