Updating ref docs to include the metrics bucket information for connection histograms

[samsp-msft]

Summary

We default histogram buckets to a size that makes sense for requests, but is not ideal for connections. This change provides longer durations for connections so that the upper bound is 5min. Connections may last longer than that, but the performance difference will be negligible after 10s of seconds, so seems like a good upper bound, while still providing granularity at the lower values, and using an approximate doubling of each bucket size.

Related to open-telemetry/opentelemetry-dotnet#5008,
open-telemetry/opentelemetry-dotnet#4922

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Internal previews

📄 File	🔗 Preview link
docs/core/diagnostics/built-in-metrics-aspnetcore.md	ASP.NET Core metrics
docs/core/diagnostics/built-in-metrics-system-net.md	System.Net metrics

[noahfalk]

Adding link to JamesNK's similar change to the OTel docs: open-telemetry/semantic-conventions#283 (review)

[JamesNK]

I think this level of detail is unnecessary in the .NET docs. Most people won't know what histogram buckets are. The people who do care can look at the spec in the OTEL repo for more information.

[JamesNK]

I said this wasn’t necessary?

[gewarren]

@IEvangelist Revert?

[IEvangelist]

@gewarren - I guess, I also don't think it hurts to have it. It seems valuable, I'd personally rather read this alongside the .NET bits that discuss this sort of thing, and I would likely avoid reading the OTEL spec. That's why I merged it... Y'all can revert it if you think it's really that unnecessary, otherwise leave it. 🤷🏼‍♂️