Reduce flakiness by waiting before pipeline hover

What does this MR do?

Adds a wait_for_requests before hovering pipeline elements on the page, to prevent them from failing randomly.

Screenshots (strongly suggested)

N/A

Does this MR meet the acceptance criteria?

Conformity

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  • I have included a changelog entry.
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Availability and Testing

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

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Related to #325950 (closed)