Fix a test that only pass on retry

What does this MR do?

This test would only pass after a retry. We change the stubbing to be at a upper level, and also use .at_least(:once) to ensure all the calls are stubbed.

Does this MR meet the acceptance criteria?

Conformity

• Code review guidelines
• Merge request performance guidelines
• Style guides
• Separation of EE specific content

Closes #211795 (closed).