Fix mx-puppet-discord container image repository URL

Fixup for d8a19e5bf9

roles/matrix-bridge-mx-puppet-discord/defaults/main.yml

@@ -21,7 +21,7 @@ matrix_mx_puppet_discord_container_image_self_build_dockerfile_path: "docker/Doc
 matrix_mx_puppet_discord_container_http_host_bind_port: ''
 
 matrix_mx_puppet_discord_version: latest
-matrix_mx_puppet_discord_docker_image: "{{ matrix_mx_puppet_discord_docker_image_name_prefix }}beeper/mx-puppet-monorepo:{{ matrix_mx_puppet_discord_version }}"
+matrix_mx_puppet_discord_docker_image: "{{ matrix_mx_puppet_discord_docker_image_name_prefix }}beeper/mx-puppet-monorepo/discord:{{ matrix_mx_puppet_discord_version }}"
 matrix_mx_puppet_discord_docker_image_name_prefix: "{{ 'localhost/' if matrix_mx_puppet_discord_container_image_self_build else 'registry.gitlab.com/' }}"
 matrix_mx_puppet_discord_docker_image_force_pull: "{{ matrix_mx_puppet_discord_docker_image.endswith(':latest') }}"