fix depth counter in UrlJob

regression from adf4d661

It would either stop at the first level (-g) or go infinitely deep (-G)
Going down to for example level 3 with -ggg didn't work.

gallery_dl/job.py

@@ -626,7 +626,7 @@ class UrlJob(Job):
             extr = extractor.find(url)
 
         if extr:
-            self.status |= self.__class__(extr, self).run()
+            self.status |= self.__class__(extr, self, self.depth + 1).run()
         else:
             self._write_unsupported(url)