fix: allow newer versions of node

Author: dessant

package.json

@@ -36,8 +36,7 @@
     "standard-version": "^4.4.0"
   },
   "engines": {
-    "node": "8.9.0",
-    "npm": "5.5.1"
+    "node": ">=8.9.0"
   },
   "keywords": [
     "github",