[hosting-logs] Add WithLogging

[CodeBlanch]

Relates to #4433

Changes

• Adds WithLogging extension on OpenTelemetryBuilder

Details

We're getting into the more interesting bits of this effort!

The current design on this PR is these 3 things are equivalent:

• Traditional API:

  appBuilder.Logging.AddOpenTelemetry();

• New API:

  appBuilder.Services.AddOpenTelemetry().WithLogging();

• Both APIs:

  // Both may be called. Only a single LoggerProvider (OTel) and ILoggerProvider (.NET) will exist
  appBuilder.Logging.AddOpenTelemetry();
  appBuilder.Services.AddOpenTelemetry().WithLogging();

WithLogging doesn't necessarily need to exist and/or doesn't need to turn on the ILogger integration. Discussed this with @noahfalk a bit and we felt this was reasonable. But open to ideas/discussions/suggestions.

Merge requirement checklist

• CONTRIBUTING guidelines followed (nullable enabled, static analysis, etc.)
• Unit tests added/updated

[alanwest]

WithLogging doesn't necessarily need to exist and/or doesn't need to turn on the ILogger integration

I understand what you're saying, but I will assert that it does need to exist. I think consistency is important. OpenTelemetry has conditioned folks to think about telemetry as metrics, traces, and logs. Good to reenforce that conditioning 😄

[codecov]

Codecov Report

Merging #4483 (cd27237) into main (5768a75) will increase coverage by 0.14%.
The diff coverage is 100.00%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4483      +/-   ##
==========================================
+ Coverage   85.13%   85.28%   +0.14%     
==========================================
  Files         315      315              
  Lines       12536    12549      +13     
==========================================
+ Hits        10673    10702      +29     
+ Misses       1863     1847      -16     

Impacted Files	Coverage Δ
...ing/Implementation/HostingExtensionsEventSource.cs	100.00% <100.00%> (ø)
...s.Hosting/Implementation/TelemetryHostedService.cs	100.00% <100.00%> (ø)
...lemetry.Extensions.Hosting/OpenTelemetryBuilder.cs	100.00% <100.00%> (+36.36%)	⬆️

... and 9 files with indirect coverage changes

[CodeBlanch]

FYI I pushed an update so that OpenTelemetryBuilder.ConfigureResource will also apply to logging.

On that topic...

What makes OpenTelemetryBuilder exciting is it gives us a place to do cross-cutting things. @noahfalk and I discussed possibly in the future having...

appBuilder.Services.AddOpenTelemetry()
  .ConfigureResource(...)
  .AddOtlpExporter() // Turns on OtlpExporter for all signals
  .WithTracing()
  .WithMetrics()
  .WithLogging();