fix: complete exception handling for UpstashRedisEntityStore (#31893)

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Author: MichaelLi65535

libs/langchain/langchain/memory/entity.py

@@ -126,8 +126,10 @@ def __init__(
 
         try:
             self.redis_client = Redis(url=url, token=token)
-        except Exception:
-            logger.error("Upstash Redis instance could not be initiated.")
+        except Exception as exc:
+            error_msg = "Upstash Redis instance could not be initiated"
+            logger.error(error_msg)
+            raise RuntimeError(error_msg) from exc
 
         self.session_id = session_id
         self.key_prefix = key_prefix