Merge branch 'docs-anchors6-ci' into 'master'

doc/ci/README.md

...i/examples/devops_and_game_dev_with_gitlab_ci_cd/index.md

doc/ci/examples/laravel_with_gitlab_and_envoy/index.md

doc/ci/examples/test-scala-application.md

doc/ci/examples/test_phoenix_app_with_gitlab_ci_cd/index.md

doc/ci/permissions/README.md

doc/ci/review_apps/index.md

doc/ci/services/README.md

doc/ci/services/postgres.md

doc/ci/triggers/README.md

doc/ci/variables/README.md

doc/ci/variables/where_variables_can_be_used.md

doc/user/admin_area/settings/continuous_integration.md

doc/user/gitlab_com/index.md

doc/user/group/clusters/index.md

doc/user/project/clusters/index.md

doc/user/project/integrations/prometheus.md

doc/user/project/new_ci_build_permissions_model.md

doc/user/project/pages/introduction.md

doc/user/project/pipelines/job_artifacts.md