Dequarantine pages_pipeline_spec e2e test

What does this MR do?

This test was previously failing in Staging from #296937 (closed) . The test was then fixed by !51234 (merged) .

This MR will dequarantine the previously failing spec.

Closes #296937 (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