Merge pull request #506 from cookiecutter-flask/dependabot/npm_and_yarn/{{cookiecutter.app_name}}/css-loader-tw-3.0.0

Update css-loader requirement from ^2.1.1 to ^3.0.0 in /{{cookiecutter.app_name}}

{{cookiecutter.app_name}}/package.json

@@ -35,7 +35,7 @@
     "babel-loader": "^8.0.6",
     "babel-preset-env": "^1.7.0",
     "concurrently": "^4.1.0",
-    "css-loader": "^2.1.1",
+    "css-loader": "^3.0.0",
     "eslint-config-airbnb-base": "^13.1.0",
     "eslint-plugin-import": "^2.17.3",
     "eslint": "^5.16.0",