obsolete: fix bug in detection of remote obsolete support

We were checking again local...

hgext/obsolete.py

@@ -1134,7 +1134,7 @@
             """wrapper around pull that pull obsolete relation"""
             self._turn_extinct_secret()
             result = opush(remote, *args, **opts)
-            if 'obsolete' in self.listkeys('namespaces') and self.obsstore:
+            if 'obsolete' in remote.listkeys('namespaces') and self.obsstore:
                 data = self.obsstore._writemarkers()
                 r = remote.pushkey('obsolete', 'dump', '',
                                    base85.b85encode(data))