Fix Required Validation of Nested Configs

[bbengfort]

Scope of changes

Fixes a bug where "required" fields in nested configs were not being properly validated. Adds tests to make sure that nested structs and pointers are correctly validated and also adds a real world example just to make sure the configuration is happening correctly.

Fixes SC-20430

Type of change

• new feature
• bug fix
• documentation
• testing
• technical debt
• other (describe)

Author checklist

• I have manually tested the change and/or added automation in the form of unit tests or integration tests
• I have added new test fixtures as needed to support added tests
• Check this box if a reviewer can merge this pull request after approval (leave it unchecked if you want to do it yourself)
• I have moved the associated Shortcut story to "Ready for Review"

Reviewer(s) checklist

• Any new user-facing content that has been added for this PR has been QA'ed to ensure correct grammar, spelling, and understandability.
• Are there any TODOs in this PR that should be turned into stories?

[bbengfort]

reflect.PtrTo is deprecated in favor of reflect.PointerTo.

[pdeziel]

Makes sense to me, thanks for fixing the bug!