Add .devcontainer config

### Description

In order to unify the development environment for anyone who wants to contribute to D2.0, I was thinking it could be helpful to include a .devcontainer configuration for those of us using VS Code. That would ensure that everyone who touches the repo does so with a consistent environment. If there's any interest in this LMK...happy to take in feedback and submit a PR.

### Epic/Story

_No response_

### Have you provided an initial effort estimate for this issue?

I have provided an initial effort estimate