suggestion: move test coverage explorer to Deploy EA

This would serve as a great test bench for how Deploy EA could be used in replacement of the [current approach](https://github.com/denoland/std/blob/b2b2d572ea1242d484333394515e92a04032fc76/.github/workflows/ci.yml#L72-L78). I already do this in [@iuioiua/redis](https://github.com/iuioiua/redis) (see https://redis-coverage.iuioiua.deno.net/). This might be best done once the `deno deploy` subcommand is available and documented.