nodejs: Fix setup-hook addNodePath quoting

The argument to addNodePath previously wasn't being quoted, leading to
problems when the argument contains characters interpreted specially by
bash

pkgs/development/web/nodejs/setup-hook.sh

···
 addNodePath () {
-    addToSearchPath NODE_PATH $1/lib/node_modules
+    addToSearchPath NODE_PATH "$1/lib/node_modules"
 }
 
 addEnvHooks "$hostOffset" addNodePath