Remove unused babel-loader from babel-preset-react-app (#6780)

Author: tlrobinson

Diff for: packages/babel-preset-react-app/package.json

@@ -32,7 +32,6 @@
     "@babel/preset-react": "7.0.0",
     "@babel/preset-typescript": "7.3.3",
     "@babel/runtime": "7.4.3",
-    "babel-loader": "8.0.5",
     "babel-plugin-dynamic-import-node": "2.2.0",
     "babel-plugin-macros": "2.5.1",
     "babel-plugin-transform-react-remove-prop-types": "0.4.24"