Summary

Quarantines the flaky workflows unit test InputWaiterTests.InputWaiter_WaitForInputAsync_CompletesWhenTimeoutExpiresAsync so the merge_group queue stops blocking on it. Tracking issue: #7360.

Why

Across the last 18 failed dotnet-build-and-test runs, this test failed 7 times, always on the net472 / windows-latest leg and always in a merge_group run. It blocks PRs that do not touch the workflows code at all: the most recent occurrence blocked #7337, which only adds a sample.

Failure signature:

Expected object to refer to System.Threading.Tasks.Task`1[System.Threading.Tasks.VoidTaskResult] {Status=WaitingForActivation}
because the wait task should complete once the timeout expires,
but found System.Threading.Tasks.Task+DelayPromise {Status=RanToCompletion}.

The test races a 300 ms SemaphoreSlim timeout against a 5 s Task.Delay guard and then asserts which one won by object identity. On the loaded net472 leg, thread pool starvation can delay the 300 ms continuation past the 5 s guard, so Task.Delay wins the WhenAny and BeSameAs fails. InputWaiter itself is behaving correctly, the test just cannot guarantee it observes the timeout in time. See #7360 for the full hypothesis.

Change

Replace [Fact] with [Fact(Skip = "Flaky in merge_group; see https://github.com/microsoft/agent-framework/issues/7360")] on the affected test, matching the convention already used for #5845, and add a short comment explaining why the existing outer bound is not sufficient.

No product code changes.

Validation

• dotnet build --tl:off --framework net472 on Microsoft.Agents.AI.Workflows.UnitTests succeeds with 0 warnings, 0 errors.
• Running the class on net472 reports total: 7, failed: 0, skipped: 1, with the skipped test being the quarantined one.
• dotnet format --verify-no-changes on the changed file passes.

Follow-up

The assertion should be rewritten so it no longer depends on scheduling latency, then the test re-enabled. Note that Task.WaitAsync(TimeSpan) is not available on net472, so any replacement has to work on .NET Framework as well. Tracked in #7360.