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What does this MR do?

add .text-center wrapper

Why was this MR needed?

Fixed in master by https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/11167

Screenshots (if relevant)

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• [ ] Documentation created/updated
• [ ] API support added
• Tests
  • Added for this feature/bug
  • All builds are passing
• Conform by the merge request performance guides
• Conform by the style guides
• Branch has no merge conflicts with master (if it does - rebase it please)
• Squashed related commits together

What are the relevant issue numbers?

Closes #32453 (closed)