Add EventListener microbenchmarks

[MihaZupan]

The networking telemetry we added to runtime in 5.0 uses EventSource and users can use EventListener to observe these events in the same process.

This PR brings a subset of Benchmarks.cs (used in dotnet/runtime#51822, dotnet/runtime#52092, dotnet/runtime#52455) to this repo to get some coverage of EventListener.

cc: @noahfalk

[danmoseley]

@MihaZupan do you plan to complete this PR? do you need a review?

I will rerun validation.

[MihaZupan]

Should just need a review

[danmoseley]

@safern or @tarekgh perhaps one of you could review? I do not have enough familiarity with this API.

[tarekgh]

This PR brings a subset of Benchmarks.cs (used in dotnet/runtime#51822, dotnet/runtime#52092, dotnet/runtime#52455) to this repo to get some coverage of EventListener.

Why not bring the whole test which testing with the http operations?

[tarekgh]

The changes here look ok to me. I'll let @noahfalk have a look too.

[noahfalk]

LGTM

[MihaZupan]

This PR brings a subset of Benchmarks.cs (used in dotnet/runtime#51822, dotnet/runtime#52092, dotnet/runtime#52455) to this repo to get some coverage of EventListener.

Why not bring the whole test which testing with the http operations?

The whole benchmark was there to estimate the benefit for real-world use cases. The benchmarks included with this PR should represent the underlying operations well and catch any regressions.

[danmoseley]

Thanks @MihaZupan . Always good to see benchmark holes plugged.