Right now CI runs all qunit/selenium testing infrastructure in the 'same' process as the MW server component, so it's not possible to determine if they're relying on local-only API calls that won't work externally (such as ResourceLoader bundle requests).

I'm not quite sure how a system would work that would let us test this, but it'd be a huge help for us to avoid repeating the situation we ended up with for Wikibase.