After coder/envbuilder#25 we can update our existing devcontainer examples to use the approaches documented there.

          We should also update our VM devcontainer templates to use docker outside docker approach. 

1. https://github.com/coder/coder/tree/main/examples/templates/aws-devcontainer
2. https://github.com/coder/coder/tree/main/examples/templates/gcp-devcontainer

Originally posted by @matifali in coder/envbuilder#25 (comment)