Transient failure in spec/helpers/tree_helper_spec.rb

As seen in https://gitlab.com/gitlab-org/gitlab-ee/builds/12737706:

  1) TreeHelper#lock_file_link exact lock returns Lock button with tooltip
     Failure/Error: expect(helper.lock_file_link(project, path)).to match("Locked by #{user.name}. You do not have permission to unlock this.")
       expected "<span data-toggle=\"tooltip\" title=\"Locked by Harriett O'Reilly. You do not have permission to unlock this\" class=\" disabled has-tooltip\">Unlock</span>" to match "Locked by Harriett O'Reilly. You do not have permission to unlock this."
     # ./spec/helpers/tree_helper_spec.rb:62:in `block (4 levels) in <top (required)>'

Finished in 12 minutes 56 seconds (files took 15.71 seconds to load)
759 examples, 1 failure

Failed examples:

rspec ./spec/helpers/tree_helper_spec.rb:59 # TreeHelper#lock_file_link exact lock returns Lock button with tooltip

Again, that's because the user name is not HTML escaped. Another case where https://gitlab.com/gitlab-org/gitlab-ce/issues/29643 would solve that.