Update HttpInListener to add gRPC tags - By storing the references to the activities created by framework and instrumentation

[utpilla]

Fixes #1740

Changes

• Updated OnStartActivity method to make both the framework and the instrumentation created activities to store each others' references
• Since the gRPC ASP.NET Core framework adds the tags grpc.method and grpc.status_code only to the activity created by the framework (Link to the framework code) we don't update the Activity.Current in OnStartActivity but we enrich the instrumentation created activity in the OnStopActivity method

[codecov]

Codecov Report

Merging #1878 (f48b8fa) into main (cb066cb) will decrease coverage by 0.54%.
The diff coverage is 77.90%.

@@            Coverage Diff             @@
##             main    #1878      +/-   ##
==========================================
- Coverage   83.77%   83.22%   -0.55%     
==========================================
  Files         187      188       +1     
  Lines        5967     6153     +186     
==========================================
+ Hits         4999     5121     +122     
- Misses        968     1032      +64     

Impacted Files	Coverage Δ
src/OpenTelemetry/Sdk.cs	100.00% <ø> (ø)
src/OpenTelemetry/Logs/OpenTelemetryLogger.cs	26.82% <20.54%> (-44.60%)	⬇️
...tation.AspNetCore/Implementation/HttpInListener.cs	81.52% <73.17%> (-5.04%)	⬇️
src/OpenTelemetry/Logs/LogRecord.cs	82.50% <77.77%> (-5.00%)	⬇️
.../OpenTelemetry/Logs/OpenTelemetryLoggerProvider.cs	77.55% <88.23%> (+7.09%)	⬆️
src/OpenTelemetry/Trace/ExceptionProcessor.cs	90.90% <90.90%> (ø)
...rc/OpenTelemetry/Trace/TracerProviderBuilderSdk.cs	89.83% <91.66%> (-0.92%)	⬇️
src/OpenTelemetry/Trace/TracerProviderSdk.cs	95.16% <98.64%> (+4.38%)	⬆️
...metryProtocol/Implementation/ActivityExtensions.cs	86.89% <100.00%> (+0.05%)	⬆️
...ry.Instrumentation.AspNet/AspNetInstrumentation.cs	100.00% <100.00%> (ø)
... and 23 more

[utpilla]

Closing this PR as we are going forward with the approach of creating the new activity with the OperationName used by the framework #1879