Implement new tier and version text style for user/project docs

doc/user/project/autocomplete_characters.md

doc/user/project/badges.md

doc/user/project/canary_deployments.md

doc/user/project/changelogs.md

doc/user/project/clusters/add_eks_clusters.md

doc/user/project/clusters/add_existing_cluster.md

doc/user/project/clusters/add_gke_clusters.md

doc/user/project/clusters/add_remove_clusters.md

doc/user/project/clusters/cluster_access.md

doc/user/project/clusters/deploy_to_cluster.md

doc/user/project/clusters/gitlab_managed_clusters.md

doc/user/project/clusters/index.md

doc/user/project/clusters/multiple_kubernetes_clusters.md

doc/user/project/clusters/runbooks/index.md

doc/user/project/code_intelligence.md

doc/user/project/codeowners/index.md

doc/user/project/codeowners/reference.md

doc/user/project/deploy_boards.md

doc/user/project/deploy_keys/index.md

doc/user/project/deploy_tokens/index.md