Skip intermediate steps in QA merge train test

What does this MR do?

Removes 2 expect statements for output that might not be seen if the merge train completes before the test gets to those statements.

Instead we skip to the merge verification, and check that the merge train pipeline passed.

See #196234 (closed)

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• [-] Separation of EE specific content