Make pslInit() returns the publicSuffixList instance used internally

Related discussion:
- https://github.com/uBlockOrigin/uBlock-issues/issues/1664#issuecomment-889647595

platform/nodejs/main.js

@@ -123,6 +123,7 @@ function pslInit(raw) {
         }
     }
     globals.publicSuffixList.parse(raw, globals.punycode.toASCII);
+    return globals.publicSuffixList;
 }
 
 function restart(lists, options = {}) {