move bnb/devenv to nodejs/devcontainer #641

per nodejs/node#39672, it seems the next steps would be to move the bnb/devenv repository into the Node.js org and to PR the .devcontainer dir to nodejs/node. I'd recommend moving it to nodejs/devcontainer.

One thing to note, we'd need to grab a Docker Hub token to publish it to the Node.js Docker Hub account to publish the image. I presume we'll want to publish it to nodejs/devcontainer to match the repo. We will need to choose some kind of name, which will need to be reflected in code here.

Worth noting that this will consume some portion of our Actions minutes. In its first run, it took about an hour and a half to build and publish on the default 2 core runner. I've presently set it up to run nightly, though the cron can be changed through normal means in GitHub. I've talked a bit with the Actions team and it seems that we'd potentially be able to get dedicated runners for this workload - I'll follow up with them once we've moved the repo into the org ❤️

Happy to do this but want to get the appropriate approvals, of course :)