Change value sent for 'None of the above' option for conditions

[SamJamCul]

What problem does this pull request solve?

https://trello.com/c/2H6cVned/2228-routes-based-on-none-of-the-above-answers-do-not-work

When creating or updating a condition for an optional selection question, we've been saving the option 'None of the above' in our database as the answer value none_of_the_above. This has had the effect of not functioning in forms runner, as it's compared to the actual answer value None of the above. This PR goes in hand with govuk-forms/forms-api#733 to ensure that the answer value missing error now avoids triggering when the answer value is None of the above.

The change in this PR makes sure that we're saving the answer value for a condition as None of the above which in turn means runner will correctly compare against the actual answer value when given.

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• Do the end to end tests need updating before these changes will pass?
• Has all relevant documentation been updated?

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[github-actions]

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