concurrent + yarn : ENOTEMPTY dir not empty npm-lodash...

When I run my setup script in circle ci using npm-utils' `concurrent` to `yarn` 3 directories at once it fails. Changing concurrent to series and it passes.

I think this maybe the same issue: https://github.com/yarnpkg/yarn/issues/2531#issuecomment-297130086
and according to that link it's resolved by:
```
concurrently -r -k \"yarn run db\" \"yarn run dev\"
```

**Here's the log:**

```
$ npm start setup

> typescript-react-asteroid-meteor@1.0.0 start /home/ubuntu/web-admin
> nps "setup"

nps is executing `setup` : nps scrub.yarn && nps setup.all
nps is executing `scrub.yarn` : yarn cache clean
yarn cache v0.27.5
⠁ ⠂ ⠄ ⡀ ⢀ ⠠ ⠐ ⠈ ⠁ ⠂ ⠄ ⡀ ⢀ success Cleared cache.
Done in 1.47s.
nps is executing `setup.all` : node node_modules/concurrently/src/main.js --kill-others-on-fail --prefix-colors "bgBlue.bold,bgMagenta.bold,bgGreen.bold" --prefix "[{name}]" --names "setup.meta,setup.client,setup.server" 'nps setup.meta' 'nps setup.client' 'nps setup.server'
[setup.meta] nps is executing `setup.meta` : yarn
[setup.client] nps is executing `setup.client` : cd www && cd client && yarn add -E asteroid@2.0.3
[setup.server] nps is executing `setup.server` : cd www && cd server && yarn
[setup.client] yarn add v0.27.5
[setup.meta] yarn install v0.27.5
[setup.client] [1/4] Resolving packages...
[setup.server] yarn install v0.27.5
[setup.meta] [1/4] Resolving packages...
[setup.server] [1/4] Resolving packages...
[setup.meta] success Already up-to-date.
[setup.meta] Done in 1.44s.
[setup.meta] nps setup.meta exited with code 0
[setup.server] [2/4] Fetching packages...
[setup.client] [2/4] Fetching packages...

[setup.client] error An unexpected error occurred: "ENOTEMPTY: directory not empty, rmdir '/home/ubuntu/.cache/yarn/v1/npm-lodash-4.17.4-78203a4d1c328ae1d86dca6460e369b57f4055ae'".
[setup.client] info If you think this is a bug, please open a bug report with the information provided in "/home/ubuntu/web-admin/www/client/yarn-error.log".
[setup.client] info Visit https://yarnpkg.com/en/docs/cli/add for documentation about this command.
[setup.client] The script called "setup.client" which runs "cd www && cd client && yarn add -E asteroid@2.0.3" failed with exit code 1 https://github.com/kentcdodds/nps/blob/v5.7.0/other/ERRORS_AND_WARNINGS.md#failed-with-exit-code
[setup.client] nps setup.client exited with code 1
--> Sending SIGTERM to other processes..

[setup.server] nps setup.server exited with code null
The script called "setup.all" which runs "node node_modules/concurrently/src/main.js --kill-others-on-fail --prefix-colors "bgBlue.bold,bgMagenta.bold,bgGreen.bold" --prefix "[{name}]" --names "setup.meta,setup.client,setup.server" 'nps setup.meta' 'nps setup.client' 'nps setup.server'" failed with exit code 1 https://github.com/kentcdodds/nps/blob/v5.7.0/other/ERRORS_AND_WARNINGS.md#failed-with-exit-code
The script called "setup" which runs "nps scrub.yarn && nps setup.all" failed with exit code 1 https://github.com/kentcdodds/nps/blob/v5.7.0/other/ERRORS_AND_WARNINGS.md#failed-with-exit-code
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! typescript-react-asteroid-meteor@1.0.0 start: `nps "setup"`
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the typescript-react-asteroid-meteor@1.0.0 start script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR! /home/ubuntu/.npm/_logs/2017-08-18T22_51_38_094Z-debug.log

npm start setup returned exit code 1

Action failed: npm start setup
```

Reproduce the failure by running the three Yarn commands concurrently, then compare it with the passing serial setup. Start at the mentioned concurrently entry point, node_modules/concurrently/src/main.js, and review the linked Yarn issue. Done means the concurrency interaction is confirmed with a focused regression test or its limitation and workaround are documented.

Written by the indexing model from the issue text.