Task #8887: check for any fields in update

SAS/ResourceAssignment/ResourceAssignmentDatabase/radb.py

@@ -805,6 +805,7 @@ class RADatabase:
             fields.append('user_id')
             values.append(user_id)
 
+        if fields and values:
             values.append(task_id)
 
             query = '''UPDATE resource_allocation.resource_claim