Remove eslint-plugin-react from devDependencies

It's already in optionalDependencies.

Author: fatfisz

package.json

@@ -23,7 +23,6 @@
     "eslint": "4.3.0",
     "eslint-config-prettier": "2.3.0",
     "eslint-plugin-prettier": "2.1.2",
-    "eslint-plugin-react": "7.1.0",
     "prettier": "1.5.3"
   },
   "scripts": {