[BUG] Tests fail in CI - investigation needed

[alessandrofelder]

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• OS: [e.g. Linux, Windows, macOS] For macOS, please specify if you have an Intel or M1 CPU (M1 is likely if your mac is new).
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[adamltyson]

Test failures seem to be due to slow download of atlases (related to brainglobe/brainglobe-atlasapi#407).