Fix System.Net.Sockets telemetry

[MihaZupan]

Includes:

• System.Net.NameResolution telemetry fix outlined by @ManickaP in Socket.Connect(Start|Stop) activity ID missmatch on Windows #41670 (comment) - Stop wasn't called in the same scope as start
• Changes to TestEventListener to allow for listening to multiple EventSources (enabling activity tracking in tests)
• Workaround for EventWrittenEventArgs bug (EventSource EventWrittenEventArgs.ActivityId isn't always set #42128) in test code only
• Socket changes to log correct events within correct execution contexts
• Tests for System.Net.Security telemetry

Before, we were logging Start events after capturing the execution context and calling Stop before restoring it.
The PR creates a common point OnCompletedInternal that is called when the execution context is restored from both sync and async completions.

Fixes #41670

[ghost]

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

[MihaZupan]

CC @josalem for TestEventListener code changes

[josalem]

Changes RE: #42128 look good to me 👍

[MihaZupan]

/azp run runtime-libraries-coreclr outerloop

[MihaZupan]

/azp run runtime-libraries-coreclr outerloop

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[MihaZupan]

Test failures unrelated:
#40798, #41531, #41953, #41929, #42722, #41606, #42724

[MihaZupan]

/backport to release/5.0-rc2

[github-actions]

Started backporting to release/5.0-rc2: https://github.com/dotnet/runtime/actions/runs/272073672

[github-actions]

@MihaZupan backporting to release/5.0-rc2 failed, the patch most likely resulted in conflicts:

$ git am --3way --ignore-whitespace --keep-non-patch changes.patch

Applying: Correct NameResolutionTelemetry logic
Applying: Enable listening to multiple sources with TestEventListener
Applying: Workaround EventWrittenEventArgs bug when the EventArgs are stored
Applying: Correct System.Net.Sockets Telemetry
Applying: Avoid using value tuple in TestEventListener
Applying: Remove unnecessary argument to OnCompletedInternal
Applying: Remove redundant Telemetry.IsEnabled check
Applying: Log Connect/Accept start before the initial context capture
Applying: Use SocketHelperBase in Accept tests
Applying: Avoid duplicate events for BeginConnect without ConnextEx support
Applying: Enable Sync Socket tests
Applying: Revert unrelated SocketPal change
Applying: Log the correct ErrorCode in case of socket disposal
Applying: Add more info on TelemetryTest timeout
Applying: Add PlatformSpecific attribute to ConnectFailure test
Applying: Add missing BeginConnect AfterConnect call on sync failure
error: sha1 information is lacking or useless (src/libraries/System.Net.Sockets/src/System/Net/Sockets/Socket.cs).
error: could not build fake ancestor
hint: Use 'git am --show-current-patch=diff' to see the failed patch
Patch failed at 0016 Add missing BeginConnect AfterConnect call on sync failure
When you have resolved this problem, run "git am --continue".
If you prefer to skip this patch, run "git am --skip" instead.
To restore the original branch and stop patching, run "git am --abort".
Error: The process '/usr/bin/git' failed with exit code 128

Please backport manually!