No. It would be really bad if the jobs running in the container could change things like app.yml. Actually, a good security practice is to put stuff like S3 keys in the yml file so that they are hidden from the Discourse interface.
Again, it’s very rare that you make changes like what domains need to be redirected, and they require other things, like DNS settings. The time to do it is when you set up Discourse, and when you set up Discourse, you’re mucking with the yml file.