ADD guidance and links to instrument, collect, and analyze metrics on Azure app services.

### Description
**Low priority -- cancel? **

Let's provide guidance and links to instrument, collect, and [analyze metrics on Azure app services](https://learn.microsoft.com/en-us/azure/azure-monitor/app/opentelemetry-enable?tabs=aspnetcore#enable-azure-monitor-opentelemetry-for-net-nodejs-python-and-java-applications).

Related https://github.com/dotnet/docs/issues/42026

### Page URL

https://learn.microsoft.com/en-us/aspnet/core/log-mon/metrics/metrics?view=aspnetcore-8.0

### Content source URL

https://github.com/dotnet/AspNetCore.Docs/blob/main/aspnetcore/log-mon/metrics/metrics.md

### Document ID

fc4aa26a-a037-2bd9-f313-e3073d6b8232

### Article author

@tdykstra