Update PoolingSession.cs

Author: KirillKurdyukov

src/Ydb.Sdk/src/Ado/Session/PoolingSession.cs

@@ -1,8 +1,3 @@
-// This file contains session pooling algorithms adapted from Npgsql
-// Original source: https://github.com/npgsql/npgsql
-// Copyright (c) 2002-2025, Npgsql
-// Licence https://github.com/npgsql/npgsql?tab=PostgreSQL-1-ov-file
-
 using Microsoft.Extensions.Logging;
 using Ydb.Query;
 using Ydb.Query.V1;