let restricted script engine use random

spiffworkflow-backend/src/spiffworkflow_backend/services/process_instance_processor.py

@@ -5,6 +5,7 @@ import decimal
 import json
 import logging
 import os
+import random
 import re
 import time
 import uuid
@@ -319,6 +320,7 @@ class CustomBpmnScriptEngine(PythonScriptEngine):  # type: ignore
             "uuid": uuid,
             "min": min,
             "max": max,
+            "random": random,
             **JinjaHelpers.get_helper_mapping(),
         }