Closes #21611: Replace calls to .count() with .exists() (#21612)

Replace two boolean evaluations of .count() with .exists()

netbox/dcim/forms/bulk_import.py

@@ -1529,8 +1529,11 @@ class CableImportForm(PrimaryModelImportForm):
 
         model = content_type.model_class()
         try:
-            if device.virtual_chassis and device.virtual_chassis.master == device and \
-                    model.objects.filter(device=device, name=name).count() == 0:
+            if (
+                device.virtual_chassis and
+                device.virtual_chassis.master == device and
+                not model.objects.filter(device=device, name=name).exists()
+            ):
                 termination_object = model.objects.get(device__in=device.virtual_chassis.members.all(), name=name)
             else:
                 termination_object = model.objects.get(device=device, name=name)

netbox/vpn/models/l2vpn.py

@@ -126,8 +126,8 @@ class L2VPNTermination(NetBoxModel):
         if self.assigned_object:
             obj_id = self.assigned_object.pk
             obj_type = ObjectType.objects.get_for_model(self.assigned_object)
-            if L2VPNTermination.objects.filter(assigned_object_id=obj_id, assigned_object_type=obj_type).\
-                    exclude(pk=self.pk).count() > 0:
+            terminations = L2VPNTermination.objects.filter(assigned_object_id=obj_id, assigned_object_type=obj_type)
+            if terminations.exclude(pk=self.pk).exists():
                 raise ValidationError(
                     _('L2VPN Termination already assigned ({assigned_object})').format(
                         assigned_object=self.assigned_object