add OpenTelemetry .NET Elastic's distribution (#20)

* feat: add .NET Elastic Otel distribution

* docs: add .NET distribution blog url

.github/README.md

@@ -4,6 +4,7 @@
 The following guide describes how to setup the OpenTelemetry demo with Elastic Observability using [Docker compose](#docker-compose) or [Kubernetes](#kubernetes). This fork introduces several changes to the agents used in the demo:
 
 - The Java agent within the [Ad](../src/adservice/Dockerfile.elastic) and [Fraud Detection](../src/frauddetectionservice/Dockerfile.elastic) services have been replaced with the Elastic distribution of the OpenTelemetry Java Agent. You can find more information about the Elastic distribution in [this blog post](https://www.elastic.co/observability-labs/blog/elastic-distribution-opentelemetry-java-agent).
+- The .NET agent within the [Cart service](../src/cartservice/src/Directory.Build.props) has been replaced with the Elastic distribution of the OpenTelemetry .NET Agent. You can find more information about the Elastic distribution in [this blog post](https://www.elastic.co/observability-labs/blog/elastic-opentelemetry-distribution-dotnet-applications).
 
 ## Docker compose
 

src/cartservice/src/Directory.Build.props

@@ -0,0 +1,5 @@
+<Project>
+  <ItemGroup>
+    <PackageReference Include="Elastic.OpenTelemetry" Version="1.0.0-alpha.3" />
+  </ItemGroup>
+</Project>

src/cartservice/src/Program.cs

@@ -12,6 +12,7 @@
 using Microsoft.Extensions.Logging;
 using OpenTelemetry.Instrumentation.StackExchangeRedis;
 using OpenTelemetry.Logs;
+using OpenTelemetry;
 using OpenTelemetry.Metrics;
 using OpenTelemetry.ResourceDetectors.Container;
 using OpenTelemetry.ResourceDetectors.Host;
@@ -30,7 +31,6 @@
 }
 
 builder.Logging
-    .AddOpenTelemetry(options => options.AddOtlpExporter())
     .AddConsole();
 
 builder.Services.AddSingleton<ICartStore>(x=>
@@ -65,15 +65,9 @@
     .WithTracing(tracerBuilder => tracerBuilder
         .AddRedisInstrumentation(
             options => options.SetVerboseDatabaseStatements = true)
-        .AddAspNetCoreInstrumentation()
-        .AddGrpcClientInstrumentation()
-        .AddHttpClientInstrumentation()
-        .AddOtlpExporter())
+        .AddAspNetCoreInstrumentation())
     .WithMetrics(meterBuilder => meterBuilder
-        .AddProcessInstrumentation()
-        .AddRuntimeInstrumentation()
-        .AddAspNetCoreInstrumentation()
-        .AddOtlpExporter());
+        .AddAspNetCoreInstrumentation());
 OpenFeature.Api.Instance.AddHooks(new TracingHook());
 builder.Services.AddGrpc();
 builder.Services.AddGrpcHealthChecks()