chore(deps): update dependency tslint to v5.20.1

Author: renovate-bot

package.json

@@ -60,7 +60,7 @@
     "rollup-plugin-node-builtins": "^2.1.2",
     "rollup-plugin-node-globals": "^1.4.0",
     "standard-version": "5.0.2",
-    "tslint": "5.16.0",
+    "tslint": "5.20.1",
     "tslint-react": "4.0.0",
     "workbox-build": "4.3.1"
   },