[EE] Retry the first login page validation

What does this MR do?

EE port of CE MR: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/29100

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation created/updated or follow-up review issue created
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• Separation of EE specific content