Ensures the idempotency of the Netbox modules when custom_fields are used. (#839)

Author: cfiehe

plugins/module_utils/netbox_utils.py

@@ -1272,6 +1272,13 @@ def _update_netbox_object(self, data):
         if serialized_nb_obj.get("vcpus") and data.get("vcpus") and version_pre_30:
             updated_obj["vcpus"] = "{0:.2f}".format(data["vcpus"])
 
+        if serialized_nb_obj.get("custom_fields"):
+            serialized_nb_obj["custom_fields"] = {
+                key: value
+                for key, value in serialized_nb_obj["custom_fields"].items()
+                if value is not None
+            }
+
         if serialized_nb_obj == updated_obj:
             return serialized_nb_obj, None
         else: