Derek Herman

Fix media upload

2

Currently you cannot upload media to the container.

Cannot run npm install from container

1

If you run `npm run docker -- npm install` from the container then you will get an error when composer tries to run. ``` npm WARN lifecycle @xwp/[email protected]~postinstall: cannot run...

## Feature description It was suggested we use the same [remark-frontmatter](https://www.npmjs.com/package/remark-frontmatter) that web.dev uses to lint the frontmatter in our Markdown files. We should also implement basic`.md` linting in this...