chore(package): update css-loader to version 3.2.1

Closes #35

Author: greenkeeper[bot]

package.json

@@ -66,7 +66,7 @@
     "conventional-github-releaser": "2.0.2",
     "copy-webpack-plugin": "^5.0.2",
     "core-js": "^2.6.0",
-    "css-loader": "^2.1.1",
+    "css-loader": "^3.2.1",
     "cssnano": "^4.1.7",
     "del": "3.0.0",
     "gulp": "3.9.1",