[QUIC] SendMoreThanStreamLimitRequestsConcurrently_LastWaits on Mocks hangs in CI

[ManickaP]

SocketsHttpHandlerTest_Http3_Mock.SendMoreThanStreamLimitRequestsConcurrently_LastWaits(10) will regularly hang in CI.
Discovered in #52704.

I'm unable to reproduce locally, even with the test running in a loop for more than an hour.

Test is disable via a condition in code:

// This combination leads to a hang manifesting in CI only. Disabling it until there's more time to investigate.
if (this.UseQuicImplementationProvider == QuicImplementationProviders.Mock)
{
    return;
}

Update: Seems like the first run of this tends to timeout (now it's the 100), disabling all mock runs for now.

[ghost]

Tagging subscribers to this area: @dotnet/ncl
See info in area-owners.md if you want to be subscribed.

Issue Details

---

SocketsHttpHandlerTest_Http3_Mock.SendMoreThanStreamLimitRequestsConcurrently_LastWaits(10) will regularly hang in CI.
Discovered in #52704.

I'm unable to reproduce locally, even with the test running in a loop for more than an hour.

Test is disable via a condition in code:

// This combination leads to a hang manifesting in CI only. Disabling it until there's more time to investigate.
if (streamLimit == 10 && this.UseQuicImplementationProvider == QuicImplementationProviders.Mock)
{
    return;
}

Author:	ManickaP
Assignees:	-
Labels:	area-System.Net.Quic, disabled-test
Milestone:	-

[ManickaP]

I spun up a new issue.

[ManickaP]

#70421