Profile: Correctly handle not existing vcard

gajim/gtk/profile.py

@@ -140,6 +140,9 @@ def _on_vcard_received(self, task):
             log.info('Error loading VCard: %s', error)
             self._current_vcard = VCard()
 
+        if self._current_vcard is None:
+            self._current_vcard = VCard()
+
         self._load_avatar()
         self._vcard_grid.set_vcard(self._current_vcard.copy())
         self._ui.profile_stack.set_visible_child_name('profile')