chore(package): update rollup-plugin-json to version 4.0.0

Author: greenkeeper[bot]

package.json

@@ -67,7 +67,7 @@
     "rollup": "^1.6.0",
     "rollup-plugin-babel": "^4.0.3",
     "rollup-plugin-commonjs": "^9.0.0",
-    "rollup-plugin-json": "^3.0.0",
+    "rollup-plugin-json": "^4.0.0",
     "rollup-plugin-node-resolve": "^4.0.1",
     "rollup-plugin-uglify": "^6.0.0",
     "rollup-watch": "^4.3.1"