add a11y color tests

[simjes]

Tries to address #31. It doesn't look too good though on the results looking at tests/a11y-test-results.txt.

tests/a11y-test-results.txt is not the result of running the expect which is in the draft request, it was the result of a less memory consuming assertion: expect(accessibilityScanResults.violations.length).toEqual(0)

It generates tests for every language and every theme, which amounts to over 9000 tests. It runs out of memory when it tries to write the test result to file, so keeping this as draft as it needs some more work before we can have a file that we can process and show in a list.

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