Update System.Net.Security Telemetry tests

[MihaZupan]

Updated the NetSecurity telemetry tests to use a WaitForEventCounters helper instead of relying on a racy Task.Delay.
Enhanced the test to also check for correct ActivityIds.

Updated the product instrumentation to use a real async method instead of .ContinueWith to ensure events fire under the right ExecutionContext. Similar to the fix in NameResolution from #42188 (#41670 (comment)).

Fixes #42613

[ghost]

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Issue Details

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Updated the NetSecurity telemetry tests to use a WaitForEventCounters helper instead of relying on a racy Task.Delay.
Enhanced the test to also check for correct ActivityIds.

Updated the product instrumentation to use a real async method instead of .ContinueWith to ensure events fire under the right ExecutionContext. Similar to the fix in NameResolution from #42188 (#41670 (comment)).

Fixes #42613

Author:	MihaZupan
Assignees:	-
Labels:	area-System.Net.Security
Milestone:	6.0.0

[MihaZupan]

/azp run runtime-libraries-coreclr outerloop

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Azure Pipelines successfully started running 1 pipeline(s).

[karelz]

@MihaZupan is it ready for re-review from @stephentoub?

[MihaZupan]

Yes. I pushed the change to always return a Task from ProcessAuthenticationAsync as suggested, which should make the logic cleaner.

[stephentoub]

Thanks.

[ghost]

Hello @MihaZupan!

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