Shorter and clearer descriptions for audit event e2e specs

What does this MR do?

Shorter and clearer descriptions for audit event e2e specs and updates bug issue link

Triggered by https://gitlab.slack.com/archives/C3JJET4Q6/p1585020908498700

Conformity

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