build: Updates content_staging based on type checking.

In the serializer, return an empty string if there is no request object.

In content_tagging, just update the type declaration to match the
expectation since it can obviously be a None type.

openedx/core/djangoapps/content_staging/serializers.py

@@ -66,7 +66,7 @@ class UserClipboardSerializer(serializers.Serializer):
         except ItemNotFoundError:
             return ""
         edit_url = xblock_studio_url(block, find_parent=True)
-        if edit_url:
+        if edit_url and request:
             return request.build_absolute_uri(edit_url)
         return ""
 

openedx/core/djangoapps/content_tagging/rest_api/v1/views.py

@@ -201,7 +201,7 @@ class ObjectTagExportView(APIView):
             def write(self, value):
                 return value
 
-        object_id: str = kwargs.get('context_id', None)
+        object_id: str | None = kwargs.get('context_id', None)
         pseudo_buffer = Echo()
 
         if not has_view_object_tags_access(self.request.user, object_id):