Add bean for CancerStudyPermissionEvaluator

[Floris-Hyve]

Add a bean for CancerStudyPermissionEvaluator instead of instantiating directly within createExpressionHandler

[Floris-Hyve]

I think there are issues with spring recognizing the CancerStudyPermissionEvaluator when it is not instantiated as a bean, which causes the expressionHandler to be set incorrectly. I think its related to how dependency injection works in spring. See below screenshots:

• Without instantiating as bean, study is accessible to a user which shouldnt have permission (can explore it too)

• As bean, study not accessible