You already have the http to https redirect covered:
Then add a router and middleware on the traefik container:
From Global redirect www to non-www with HTTPS redirection - #9 by ldez - Traefik v2 (latest) - Traefik Labs Community Forum
# Global redirection: https (www.) to https
traefik.http.routers.wwwsecure-catchall.rule: HostRegexp(`{host:(www\.).+}`)
traefik.http.routers.wwwsecure-catchall.entrypoints: websecure
traefik.http.routers.wwwsecure-catchall.tls: true
traefik.http.routers.wwwsecure-catchall.middlewares: wwwtohttps
# middleware: http(s)://(www.) to https://
traefik.http.middlewares.wwwtohttps.redirectregex.regex: ^https?://(?:www\.)?(.+)
traefik.http.middlewares.wwwtohttps.redirectregex.replacement: https://${1}
traefik.http.middlewares.wwwtohttps.redirectregex.permanent: true