* feat: github-auth flag
This will allow injecting credentials into code-server if you already
have them.
* Update Code
Contains the GitHub auth changes.
* Add e2e test for GitHub token
* Add test extension
This will let us test extension-related features (like the proxy URI).
I removed the environment variables in the script because they override
the ones you set yourself. We still set defaults in constants.ts.
* Add changelog entry for VSCODE_PROXY_URI
* Add terminal test for VSCODE_PROXY_URI
* Update VS Code
This adds the VSCODE_PROXY_URI environment variable.
