Resolve "Security reports app tests are not 100% correct"

What does this MR do?

1. Exports store as a factory function. It's used in 2 apps, although none of them is used at the same time, this avoids any possible problems.

2. Fixes a broken test that was receiving 2 network requests

Does this MR meet the acceptance criteria?

• Tests added for this feature/bug
• Conform by the code review guidelines
  • Has been reviewed by a Frontend maintainer
• EE specific content should be in the top level /ee folder
• Conform by the merge request performance guides
• Conform by the style guides
• If you have multiple commits, please combine them into a few logically organized commits by squashing them

What are the relevant issue numbers?

Closes #5831 (closed)