jsauthority: pass "%s" format string to remaining report function

commit 00adeee1 attempted to add a "%s" format string to the
two JS_Report invocations that needed it, but somehow only got
one them.

This commit gets the other one.

https://bugzilla.gnome.org/show_bug.cgi?id=105865

src/polkitbackend/polkitbackendjsauthority.cpp

@@ -1292,7 +1292,7 @@ js_polkit_log (JSContext  *cx,
   JS::CallArgs args = JS::CallArgsFromVp (argc, vp);
 
   s = JS_EncodeString (cx, args[0].toString ());
-  JS_ReportWarningUTF8 (cx, s);
+  JS_ReportWarningUTF8 (cx, "%s", s);
   JS_free (cx, s);
 
   ret = true;