Enhance the instrumentation-http hooks or add new ones to allow users to add their own attributes to the server and client metrics

[mkrudele]

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Is your feature request related to a problem? Please describe.

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Describe the solution you'd like

This is related to https://github.com/open-telemetry/opentelemetry-js/issues/3683.
Our need is to add extra attributes to the http_server and http_client metrics provided by the HTTP instrumentation.
That's not actually possible because of this https://github.com/open-telemetry/opentelemetry-js/issues/3683#issuecomment-1477373472.
Ideally we would use the requestHook https://open-telemetry.github.io/opentelemetry-js/interfaces/_opentelemetry_instrumentation_http.HttpInstrumentationConfig.html#requestHook to inject custom attributes to those metrics, but any additional hook would work as far as we can add additional attributes to http server and client duration metrics.

Describe alternatives you've considered

The alternative is actually using the instrumentation-express, which adds the http_route to the server metric. However, we have the need to add additional custom attributes to both, server and client metrics.

Additional context

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