Add CSS compilation to tests

[maxkadel]

What maintenance needs to be done?

In order to test CSS, we need to compile it for the tests. This is not always needed; however, in cases like the header, where we show one application name on small screen sizes and a different one on larger screen sizes, it would be nice to be able to test for which element is visible.

Level of urgency

• High
• Moderate
• Low

Why is this maintenance needed?

• To ensure that we show only one application name at a time, we should test for element visibility, and in order to do so, we need to compile CSS for at least some of the tests.

Acceptance criteria

• The test suite is not significantly slower
• We can accurately test for whether an element is visible or not (using isVisible or similar)

Implementation notes, if any