Add additional Screenshot-based UI testing

[Supereg]

Problem

Currently, we test some SpeziViews components that are layout-based via the SnapshotTesting framework. This ensures that the views don't unexpectedly change visually between releases.

Solution

We should use this approach for more View components within SpeziViews to ensure consistent styling for all ui components.

Additional context

No response

Code of Conduct

• I agree to follow this project's Code of Conduct and Contributing Guidelines