Improve UX of `yarn release`

If `package.json` has:

```
"scripts": {
"release": "aegir release"
```

and I run `yarn release` instead of `npm run release` it fails at the very last stage of publishing to NPM:

```
npm ERR! 401 Unauthorized - PUT https://registry.yarnpkg.com/is-ipfs - You must be logged in to publish packages.
```

I did not look at the URL and assumed i got logged out from NPM, to I've run `npm login` and then retried with `yarn release`, which failed again :upside_down_face:

I feel bit ashamed that it took me two retries to squint and see that its `yarnpkg.com`, but I suspect most of folks would do the same, so perhaps it worth addressing somehow?

Are we able to fix this so it just works under `yarn`?
If not, at least detect `release` runs under `yarn` and simply return error asking to run it via `npm` ?