WIP: Add tests visual review MVC

What does this MR do?

This adds a companion test for the script in !27518 (merged).

It's a bit of a strange problem to solve, mounting and testing a script we write but do not run in our app. This is a spot to figure out if this is the right approach to test it and for me to get feedback on my first rspec + capybara test. 😁

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation created/updated or follow-up review issue created
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Performance and testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.