refactor: update branch handling in changelog and allow clearing optional attributes if mutated

Author: minitriga

changelog/535.fixed.md

@@ -1 +1 @@
-Fix branch handling in `_run_transform` and `execute_graphql_query` functions in Infrahubctl to use environment variables for branch management. 
+Fix branch handling in `_run_transform` and `execute_graphql_query` functions in Infrahubctl to use environment variables for branch management.

changelog/549.fixed.md

@@ -1 +1 @@
-Allow the ability to clear optional dropdown attributes by setting them to None.
+Allow the ability to clear optional attributes by setting them to None if they have been mutated by the user.

infrahub_sdk/node/attribute.py

@@ -76,7 +76,7 @@ def _generate_input_data(self) -> dict | None:
         variables: dict[str, Any] = {}
 
         if self.value is None:
-            if self._schema.kind == "Dropdown" and self._schema.optional:
+            if self._schema.optional and self.value_has_been_mutated:
                 data["value"] = None
             return data