A teacher can choose one of 4 options for publishing choice results

1. Login as a teacher, update a choice and set 'Publish results' to 'Do not publish results to students'.
2. Login as student1, add a choice response and check that the results are not displayed.
3. Login as a teacher, update the choice and set 'Publish results' to 'Always show results to students'.
4. Login as student2 and check that the results are displayed.
5. Login as a teacher, update the choice and set 'Publish results' to 'Show results to students after they answer'.
6. Login as student2, add a choice response and check that the results are only displayed after answering.
7. Login as a teacher, update the choice and set 'Publish results' to 'Show results to students only after the choice is closed'.
8. Login as student3, add a choice response and check that the results are not displayed.
9. Login as a teacher, update the choice and close it by setting an available to date.
10. Login as student3 again and check that the results are now displayed.