Fix error on should_skip_distributed_tracing? on ethon instrumentation

Author: vpellan

lib/datadog/tracing/contrib/ethon/easy_patch.rb

@@ -114,7 +114,10 @@ def datadog_before_request(continue_from: nil)
                 datadog_trace.sampling_priority = Tracing::Sampling::Ext::Priority::AUTO_REJECT
               end
 
-              unless Tracing::Distributed::Helpers.should_skip_distributed_tracing?(datadog_configuration, trace: trace)
+              unless Tracing::Distributed::Helpers.should_skip_distributed_tracing?(
+                datadog_configuration,
+                trace: datadog_trace
+              )
                 @datadog_original_headers ||= {}
                 Contrib::HTTP.inject(datadog_trace, @datadog_original_headers)
                 self.headers = @datadog_original_headers