Fix/apply 1178 optional working preferences questions

[KoWeiJAC]

What's included?

Closes #1178

Who should test?

✅ Product owner ✅ Developers ✅ UTG

How to test?

• Apply the vacancy for V2 working preferences: https://jac-apply-develop--pr1206-fix-apply-1178-optio-vzh8kxoo.web.app/vacancy/WazMCe66xTnbKBxcr7b7/
  • Location preferences
    • Leave optional questions empty, it should allow Save and continue
  • Jurisdiction Preferences
    • Leave optional questions empty, it should allow Save and continue
  • Additional Preferences
    • Leave optional questions empty, it should allow Save and continue
• Apply the vacancy for V1 working preferences: https://jac-apply-develop--pr1206-fix-apply-1178-optio-vzh8kxoo.web.app/vacancy/0WqDanorNQnQxHdanxMe/
  • Location preferences
    • All questions are optional
  • Jurisdiction Preferences
    • All questions are mandatory
  • Additional Preferences
    • All questions are mandatory

      Risk - how likely is this to impact other areas?

      🟢 No risk - this is a self-contained piece of work

Additional context

Include screen grabs, notes etc.

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PREVIEW:DEVELOP can be OFF, DEVELOP or STAGING

[github-actions[bot]]

Visit the preview URL for this PR (updated for commit 8f7d5e8):

https://jac-apply-develop--pr1206-fix-apply-1178-optio-vzh8kxoo.web.app

_{(expires Fri, 30 Aug 2024 15:02:42 GMT)}

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_{Sign: d5ac0a9c931657844a433a502135cf38aca21627}

[KoWeiJAC]

@NormaJAC For V1, based on test and code, it seems there's no mandatory settings on the admin site, the mandatory settings are fixed on apply site:

• Location preference: optional
• Jurisdiction preferences: mandatory
• Additional preferences: mandatory