Revert [sdk] Use reflection and dynamic types to start providers

[CodeBlanch]

Reverts #4151

Rolling back the reflection emit IHostedService PR so we can explore some other options. This might come back pending that exploration.

[codecov]

Codecov Report

Merging #4173 (9c6a232) into main (b549e12) will decrease coverage by 0.01%.
The diff coverage is 84.37%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4173      +/-   ##
==========================================
- Coverage   85.60%   85.59%   -0.01%     
==========================================
  Files         292      293       +1     
  Lines       11467    11371      -96     
==========================================
- Hits         9816     9733      -83     
+ Misses       1651     1638      -13     

Impacted Files	Coverage Δ
...ensions.Hosting/OpenTelemetryServicesExtensions.cs	0.00% <0.00%> (ø)
...nTelemetry/Internal/OpenTelemetrySdkEventSource.cs	80.46% <ø> (+0.32%)	⬆️
src/OpenTelemetry/OpenTelemetryBuilder.cs	63.63% <ø> (ø)
...ronmentVariables/EnvironmentVariablesExtensions.cs	40.00% <40.00%> (-60.00%)	⬇️
...ing/Implementation/HostingExtensionsEventSource.cs	100.00% <100.00%> (ø)
...s.Hosting/Implementation/TelemetryHostedService.cs	100.00% <100.00%> (ø)
...s.Hosting/OpenTelemetryBuilderHostingExtensions.cs	100.00% <100.00%> (ø)
...AspNetCore/Implementation/HttpInMetricsListener.cs	74.35% <100.00%> (ø)
...ementation/HttpHandlerMetricsDiagnosticListener.cs	95.00% <100.00%> (ø)
...emetry/OpenTelemetryServiceCollectionExtensions.cs	100.00% <100.00%> (ø)
... and 3 more