[Feature] Never require asset behavioural skill assessment

[JamesHuf]

🤖 Resolves #12552

👋 Introduction

Updates the site to prevent requiring assessment for non-essential behavioural skills. Essential skills and non-essential technical skills should remain the same.

🧪 Testing

1. Create a pool with both an essential skill and an asset behavioural skill.
2. Create an assessment step which assesses both skills.
3. Publish the pool filling in any other fields required.
4. Create and submit an application to the pool.
5. Navigate to view the application at admin/candidates/{candidateId}/application.
6. Confirm the essential skill appears as "To assess" and the asset skill as "Unclaimed" in the assessment step from 2.
7. Assess the essential skill as demonstrated.
8. Confirm the step appears as successful.