Update concurrently requirement from ^3.5.0 to ^4.0.1 in /{{cookiecutter.app_name}}

Updates the requirements on [concurrently](https://github.com/kimmobrunfeldt/concurrently) to permit the latest version.
- [Release notes](https://github.com/kimmobrunfeldt/concurrently/releases)
- [Commits](https://github.com/kimmobrunfeldt/concurrently/commits/v4.0.1)

Signed-off-by: dependabot[bot] <support@dependabot.com>

{{cookiecutter.app_name}}/package.json

@@ -30,7 +30,7 @@
     "babel-eslint": "^9.0.0",
     "babel-loader": "^7.0.0",
     "babel-preset-env": "^1.6.0",
-    "concurrently": "^3.5.0",
+    "concurrently": "^4.0.1",
     "css-loader": "^1.0.0",
     "eslint": "^5.3.0",
     "eslint-config-airbnb-base": "^11.2.0",