fixes #47716 where email confirmation fails after adding additional emails

What does this MR do?

Fixes a bug to call the correct class because currently resource call the wrong model class.

Are there points in the code the reviewer needs to double check?

Whether checking the class name would be a good way. All tests (including mine) seems to pass.

Why was this MR needed?

Without this fix, a user who adds a secondary email and clicks on the confirmation link will get an error. This is a high priority issue (P2)

Screenshots (if relevant)

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• API support added
• Tests added for this feature/bug
• Conform by the code review guidelines
  • Has been reviewed by a UX Designer
  • Has been reviewed by a Frontend maintainer
  • Has been reviewed by a Backend maintainer
  • Has been reviewed by a Database specialist
• 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
• Internationalization required/considered
• End-to-end tests pass (package-and-qa manual pipeline job)

What are the relevant issue numbers?

issue 47716