Remove slow test marker

[adamltyson]

This PR closes #297 by removing the slow pytest marker.

I changed the test a bit, but it's still not ideal, because it changes the default brainglobe config file. It changes it back, but that's not great.

I assumed I could get around this by setting monkeypatch.setenv("BRAINGLOBE_CONFIG_DIR", str(tmp_path)), this however doesn't seem to set the config dir temporarily. I don't know if I'm monkeypatching this incorrectly, or there's a bug in the atlas api itself.

I've created this as a draft PR because I think this should be fixed, but maybe this PR should be merged and then an issue created to improve the test? This PR doesn't introduce the problem.

[alessandrofelder]

I've created this as a draft PR because I think this should be fixed, but maybe this PR should be merged and then an issue created to improve the test? This PR doesn't introduce the problem.

I don't mind either way. A new issue is probably cleaner (but also more overhead). One thing maybe worth trying (that I think would be a good idea across BrainGlobe) is to monkeypatch Path.home() for all tests when not running on CI. It looks like there's a few constant variables that need to be adapted for the patching to work. This way

• we test a slightly more real-life case on CI (Path.home() is not patched, but that's fine, because the CI does not have a user set up.)
• we locally keep ~./brainglobe/ (user data) and ~/.brainglobe-tests/.brainglobe/ (tests interacting with fake user data) always completely separate.

[adamltyson]

To simplify, I've marked this ready to review and raised #302