Update or remove ui launch button test

[jakemcdermott]

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Summary

One of the assertions in the launch button test isn't actually verifying the correct behavior.

...
    const button = wrapper.find('button');
    await act(() => button.prop('onClick')());
    wrapper.update();
    expect(wrapper.find('button').prop('disabled')).toEqual(false);
  });
...

This is something @AlexSCorey spotted during PR review and we should definitely address it when we can. We'll want to either remove the test case (if it is no longer a valid test case) or update the assertion.