Fix duplicate titles

• For https://gitlab.com/gitlab-com/gitlab-docs/issues/194, gitlab-com/gitlab-docs#195

Pages with duplicate titles:

• GitLab Pages | GitLab

  • https://docs.gitlab.com/ee/user/project/pages/
  • https://docs.gitlab.com/ee/user/project/pages/introduction.html

• | GitLab

  • https://docs.gitlab.com/ce/articles/openshift_and_gitlab/index.html
  • https://docs.gitlab.com/ee/administration/external_database.html
  • https://docs.gitlab.com/ee/administration/geo/replication/security_review.html
  • https://docs.gitlab.com/ee/articles/runner_autoscale_aws/
  • https://docs.gitlab.com/ee/container_registry/README.html
  • https://docs.gitlab.com/ee/customization/issue_closing.html
  • https://docs.gitlab.com/ee/legal/corporate_contributor_license_agreement.html
  • https://docs.gitlab.com/ee/workflow/protected_branches.html

• Labels | GitLab

  • https://docs.gitlab.com/ee/user/admin_area/labels.html
  • https://docs.gitlab.com/ee/user/project/labels.html

• Installing GitLab on Google Cloud Platform | GitLab

  • https://docs.gitlab.com/ee/install/google_cloud_platform/
  • https://docs.gitlab.com/ee/install/google_cloud_platform/index.html

• Project import/export | GitLab

  • https://docs.gitlab.com/ee/administration/raketasks/project_import_export.html
  • https://docs.gitlab.com/ee/user/project/settings/import_export.html

• Merge request approvals | GitLab

  • https://docs.gitlab.com/ee/api/merge_request_approvals.html
  • https://docs.gitlab.com/ee/user/project/merge_requests/merge_request_approvals.html

• Git LFS | GitLab

  • https://docs.gitlab.com/ee/workflow/git_lfs.html
  • https://docs.gitlab.com/ee/workflow/lfs/manage_large_binaries_with_git_lfs.html

• Merge requests | GitLab

  • https://docs.gitlab.com/ee/university/training/topics/merge_requests.html
  • https://docs.gitlab.com/ee/user/project/merge_requests/

• Webhooks | GitLab

  • https://docs.gitlab.com/ee/raketasks/web_hooks.html
  • https://docs.gitlab.com/ee/user/project/integrations/webhooks.html

• GitLab Docker images | GitLab

  • https://docs.gitlab.com/ee/install/docker.html
  • https://docs.gitlab.com/omnibus/docker/

• Features | GitLab

  • https://docs.gitlab.com/ee/development/ux_guide/features.html
  • https://docs.gitlab.com/ee/raketasks/features.html

• Using Dpl as deployment tool | GitLab

  • https://docs.gitlab.com/ce/ci/examples/deployment/README.html
  • https://docs.gitlab.com/ee/ci/examples/deployment/

• Updating GitLab via omnibus-gitlab | GitLab => omnibus-gitlab#3499 (closed)

  • https://docs.gitlab.com/omnibus/update.html
  • https://docs.gitlab.com/omnibus/update/

• GitLab CI Services | GitLab

  • https://docs.gitlab.com/ee/ci/services/
  • https://docs.gitlab.com/ee/ci/services/docker-services.html

• GitLab Flow | GitLab

  • https://docs.gitlab.com/ee/university/training/gitlab_flow.html
  • https://docs.gitlab.com/ee/university/training/topics/gitlab_flow.html

• Security | GitLab => https://gitlab.com/gitlab-org/gitlab-ce/issues/46067

  • https://docs.gitlab.com/ee/development/fe_guide/security.html
  • https://docs.gitlab.com/ee/development/new_fe_guide/development/security.html | https://docs.gitlab.com/ee/security/