chore(deps): update coturn/coturn docker tag to v4.8.0

roles/custom/matrix-coturn/defaults/main.yml

@@ -26,7 +26,7 @@ matrix_coturn_container_image_self_build_repo_version: "docker/{{ matrix_coturn_
 matrix_coturn_container_image_self_build_repo_dockerfile_path: "docker/coturn/alpine/Dockerfile"
 
 # renovate: datasource=docker depName=coturn/coturn versioning=loose
-matrix_coturn_version: 4.8.0-r0
+matrix_coturn_version: 4.8.0
 matrix_coturn_docker_image: "{{ matrix_coturn_docker_image_registry_prefix }}coturn/coturn:{{ matrix_coturn_version }}-alpine"
 matrix_coturn_docker_image_registry_prefix: "{{ 'localhost/' if matrix_coturn_container_image_self_build else matrix_coturn_docker_image_registry_prefix_upstream }}"
 matrix_coturn_docker_image_registry_prefix_upstream: "{{ matrix_coturn_docker_image_registry_prefix_upstream_default }}"