bug: Grpc requests go via proxy on Grpc.NET.Client >= 2.44

[zinal]

Bug Report

YDB dotnet SDK version: 0.8.0

Environment

Linux

Current behavior:

If:

• using Grpc.NET.Client >= 2.44
• proxy settings are defined for internet access
• with the current version of YDB SDK for .Net

Grpc.Core.RpcException
HResult=0x80131500
Message=Status(StatusCode="Internal", Detail="Error starting gRPC call. HttpRequestException: Unable to get subchannel from HttpRequestMessage. ([proxyserver.net:8080](http://proxyserver.net:8080/)) InvalidOperationException: Unable to get subchannel from HttpRequestMessage.", DebugException="System.Net.Http.HttpRequestException: Unable to get subchannel from HttpRequestMessage. ([proxyserver.net:8080](http://proxyserver.net:8080/))")
Source=Grpc.Net.Client
StackTrace:
at Grpc.Net.Client.Internal.GrpcCall`2.d72.MoveNext()
at Ydb.Sdk.Driver.d13.MoveNext()
at Ydb.Sdk.Driver.d10.MoveNext()
at Program.<

$>d0.MoveNext() in ...Program.cs:line 13
at Program.
(String[] args)
This exception was originally thrown at this call stack:
Grpc.Net.Client.Balancer.Internal.BalancerHttpHandler.OnConnect(System.Net.Http.SocketsHttpConnectionContext, System.Threading.CancellationToken)
System.Threading.Tasks.ValueTask.Result.get() in ValueTask.cs
System.Net.Http.HttpConnectionPool.ConnectToTcpHostAsync(string, int, System.Net.Http.HttpRequestMessage, bool, System.Threading.CancellationToken) in HttpConnectionPool.cs

Inner Exception 1:
HttpRequestException: Unable to get subchannel from HttpRequestMessage. ([proxyserver.net:8080](http://proxyserver.net:8080/))

Inner Exception 2:
InvalidOperationException: Unable to get subchannel from HttpRequestMessage.

Expected behavior:

Program works, instead of failing

Steps to reproduce:

Run the console application with the current YDB SDK and Grpc.NET.Client >= 2.44, as specified below.

Related code:

using Ydb.Sdk;
using Ydb.Sdk.Auth;

var config = new DriverConfig(endpoint: "grpcs://ydb.serverless.yandexcloud.net:2135",
database: "/ru-central1/aaa/bbb",
credentials: new TokenProvider("…."));

using var driver = new Driver(config: config);

await driver.Initialize();

Other information:

grpc/grpc-dotnet#2254

grpc/grpc-dotnet#2312 (comment)