maps: let get_geojson work with None as request (#42520)

combo/apps/maps/models.py

@@ -202,7 +202,7 @@ class MapLayer(models.Model):
             center_lat = float(request.GET['lat'])
             center_lng = float(request.GET['lng'])
             distance_params = True
-        except (ValueError, KeyError):
+        except (AttributeError, ValueError, KeyError):
             distance_params = False
         if request and self.geojson_accepts_circle_param and distance_params:
             req = PreparedRequest()