WIP: Dismiss popovers before they appear in QA MR tests

What does this MR do?

Popovers can get in the way of tests, so we dismiss them before visiting the MR page.

Closes #118473 (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

Availability and Testing

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