bump engine

Author: edeustace

package.json

@@ -18,7 +18,7 @@
   },
   "repository": "pie-framework/pie-cli.git",
   "engines": {
-    "node": ">=9.4.0 <10",
+    "node": ">=9.4.0",
     "npm": ">=5.6.0"
   },
   "keywords": [