Quarantine export file download spec in staging only and update issue link

What does this MR do?

1. Quarantines export file download spec in staging only due to #296212 (closed)
2. Update issue link because Maximum number of comments exceeded

Conformity

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