Fix for part serializer (#8069)

* Fix for part serializer

- Allow "revision" to accept null values
- Matches internal field

* Bump API version

src/backend/InvenTree/InvenTree/api_version.py

@@ -1,13 +1,16 @@
 """InvenTree API version information."""
 
 # InvenTree API version
-INVENTREE_API_VERSION = 249
+INVENTREE_API_VERSION = 250
 
 """Increment this API version number whenever there is a significant change to the API that any clients need to know about."""
 
 
 INVENTREE_API_TEXT = """
 
+v250 - 2024-09-04 : https://github.com/inventree/InvenTree/pull/8069
+    - Fixes 'revision' field definition in Part serializer
+
 v249 - 2024-08-23 : https://github.com/inventree/InvenTree/pull/7978
     - Sort status enums
 

src/backend/InvenTree/part/serializers.py

@@ -354,11 +354,9 @@ class PartBriefSerializer(InvenTree.serializers.InvenTreeModelSerializer):
         help_text=_('Internal Part Number'),
         max_length=100,
     )
+
     revision = serializers.CharField(
-        required=False,
+        required=False, default='', allow_blank=True, allow_null=True, max_length=100
-        allow_null=True,
-        help_text=_('Part revision or version number'),
-        max_length=100,
     )
 
     # Pricing fields
@@ -909,7 +907,7 @@ class PartSerializer(
     )
 
     revision = serializers.CharField(
-        required=False, default='', allow_blank=True, max_length=100
+        required=False, default='', allow_blank=True, allow_null=True, max_length=100
     )
 
     # Annotated fields