Collection was modified; enumeration operation may not execute

[valeraf23]

Bug Report

<PackageReference Include="OpenTelemetry" Version="1.1.0-beta4" />
<PackageReference Include="OpenTelemetry.Api" Version="1.1.0-beta4" />
<PackageReference Include="OpenTelemetry.Exporter.Console" Version="1.1.0-beta4" />
<PackageReference Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" Version="1.1.0-beta4" />
<PackageReference Include="OpenTelemetry.Extensions.Hosting" Version="1.0.0-rc5" />
<PackageReference Include="OpenTelemetry.Instrumentation.AspNetCore" Version="1.0.0-rc5" />

Symptom

            services.AddOpenTelemetryTracing(builder =>
            {
                builder.Configure(
                    (sp, b) => b.AddAspNetCoreInstrumentation());
            });

            var tracerFactory = serviceProvider.GetRequiredService<TracerProvider>();

occurred exception
System.InvalidOperationException: 'Collection was modified; enumeration operation may not execute.'

The reason that AddAspNetCoreInstrumentation method also executes builder. Configure method. But for my point of view if I can call AddAspNetCoreInstrumentation from the builder. Configure there are should not be exceptions

[CodeBlanch]

Should be fixed with #2080