chore(deps): update dependency bundlesize to v0.18.0

Author: renovate-bot

package.json

@@ -30,7 +30,7 @@
     "babel-plugin-transform-class-properties": "6.24.1",
     "babel-preset-env": "1.6.1",
     "babel-preset-react": "6.24.1",
-    "bundlesize": "0.15.3",
+    "bundlesize": "0.18.0",
     "css-loader": "0.28.7",
     "enzyme": "3.1.0",
     "eslint": "4.9.0",