Use salt instead of datetime (#8653)

If you want to kick off two runs at the same time it'll cause errors.
Use a uuid instead

libs/langchain/langchain/smith/evaluation/runner_utils.py

@@ -6,7 +6,7 @@ import asyncio
 import functools
 import itertools
 import logging
-from datetime import datetime
+import uuid
 from enum import Enum
 from typing import (
     Any,
@@ -234,12 +234,12 @@ def _get_project_name(
     """
     if project_name is not None:
         return project_name
-    current_time = datetime.now().strftime("%Y-%m-%d-%H-%M-%S")
     if isinstance(llm_or_chain_factory, BaseLanguageModel):
         model_name = llm_or_chain_factory.__class__.__name__
     else:
         model_name = llm_or_chain_factory().__class__.__name__
-    return f"{current_time}-{model_name}"
+    hex = uuid.uuid4().hex
+    return f"{hex}-{model_name}"
 
 
 ## Shared Validation Utilities