MetricReaderOptions for AddInMemoryExporter extension methods

[alanwest]

As I was working through this PR I was originally feeling "🤮 I don't like it" and then I started feeling "🤔 I suppose this could work". At first I didn't think there'd ever be the need for a periodic InMemory exporter, but I guess we do have some tests that use it.

I'll let you all be the judge. Do you find it nice to have an extension method for the InMemory exporter that allows configuring the standard options for the underlying metric reader?

[codecov]

Codecov Report

Merging #2931 (6927868) into main (843d6fd) will decrease coverage by 0.02%.
The diff coverage is 60.86%.

@@            Coverage Diff             @@
##             main    #2931      +/-   ##
==========================================
- Coverage   83.87%   83.84%   -0.03%     
==========================================
  Files         254      254              
  Lines        8918     8940      +22     
==========================================
+ Hits         7480     7496      +16     
- Misses       1438     1444       +6     

Impacted Files	Coverage Δ
...rter.InMemory/InMemoryExporterMetricsExtensions.cs	64.00% <60.86%> (-36.00%)	⬇️
...Telemetry/Internal/SelfDiagnosticsEventListener.cs	96.87% <0.00%> (-0.79%)	⬇️
...heus/Implementation/PrometheusCollectionManager.cs	82.27% <0.00%> (+2.53%)	⬆️
...emetry.Api/Internal/OpenTelemetryApiEventSource.cs	82.35% <0.00%> (+2.94%)	⬆️
...ZPages/Implementation/ZPagesExporterEventSource.cs	62.50% <0.00%> (+6.25%)	⬆️

[reyang]

I'll let you all be the judge. Do you find it nice to have an extension method for the InMemory exporter that allows configuring the standard options for the underlying metric reader?

Yes +1

[cijothomas]

I'll let you all be the judge. Do you find it nice to have an extension method for the InMemory exporter that allows configuring the standard options for the underlying metric reader?

Yes +1

The question is self-answered in this PR itself. The tests looks much nicer :)