feat: compatibility with OTEL_SDK_DISABLED

Author: bdewater-thatch

instrumentation/puma/lib/opentelemetry/instrumentation/puma/plugin.rb

@@ -34,6 +34,8 @@ def register_puma_7_events(launcher)
         end
 
         def shutdown_providers
+          return if ENV['OTEL_SDK_DISABLED'] == 'true'
+
           OpenTelemetry.tracer_provider.shutdown
           OpenTelemetry.meter_provider.shutdown if OpenTelemetry.respond_to?(:meter_provider)
           OpenTelemetry.logger_provider.shutdown if OpenTelemetry.respond_to?(:logger_provider)