Update dependencies

Author: Michiel de Jong (build server)

package-lock.json

@@ -46,7 +46,7 @@
   },
   "homepage": "https://github.com/solid/acl-check",
   "dependencies": {
-    "rdflib": "^2.0.0",
+    "rdflib": "^2.1.1",
     "solid-namespace": "^0.5.0"
   },
   "devDependencies": {