Re-add gitlab:ui:visual ci job

What does this MR do?

Re-add gitlab:ui:visual ci job that was previously reverted because the dependency version of gitlab-ui was breaking EE. It has since been resolved when we upgraded gitlab-ui to v2.1.1

Revert MR: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/25764 gitlab-ui fix MR: gitlab-ui!197 (merged)

What are the relevant issue numbers?

Closes gitlab-ui#192 (closed)

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated via this MR
• Documentation reviewed by technical writer or follow-up review issue created
• Tests added for this feature/bug
• Tested in all supported browsers
• Conforms to the code review guidelines
• Conforms to the merge request performance guidelines
• Conforms to the style guides
• Conforms to the database guides
• Link to e2e tests MR added if this MR has Requires e2e tests label. See the Test Planning Process.
• Security reports checked/validated by reviewer