MsQuicStream can leak CancellationTokenRegistrations

[MihaZupan]

While reading through #69483 I noticed that SetupWriteStartState creates a CancellationTokenRegistration, but the method may still throw, in which case the registration won't be disposed.

As a result the MsQuicStream.State will remain rooted by the (potentially user-provided) cancellation token.

cc: @rzikm @ManickaP

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Issue Details

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While reading through #69483 I noticed that SetupWriteStartState creates a CancellationTokenRegistration, but the method may still throw, in which case the registration won't be disposed.

As a result the MsQuicStream.State will remain rooted by the (potentially user-provided) cancellation token.

cc: @rzikm @ManickaP

Author:	MihaZupan
Assignees:	-
Labels:	bug, tenet-reliability, area-System.Net.Quic
Milestone:	-

[rzikm]

Duplicate of #55437

I want to tackle this once #68772 is merged, we can do additional refactorings once we don't have 3 duplicate Send*Async implementations