Fix the pulse attribute decorations on unsampled lambda spans (#92)

*Issue #, if available:*
Fix the pulse attribute decorations on unsampled lambda spans
*Description of changes:*


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Author: mxiamxia

aws-distro-opentelemetry-node-autoinstrumentation/src/aws-opentelemetry-configurator.ts

@@ -256,14 +256,13 @@ export class AwsOpentelemetryConfigurator {
 
     // Register BatchUnsampledSpanProcessor to export unsampled traces in Lambda
     // when Application Signals enabled
-    if (isLambdaEnvironment()) {
+    if (isLambdaEnvironment() && !hasCustomOtlpTraceEndpoint()) {
+      const udpSpanExporter = new OTLPUdpSpanExporter(getXrayDaemonEndpoint(), FORMAT_OTEL_UNSAMPLED_TRACES_BINARY_PREFIX);
+      const configuredExporter = AwsMetricAttributesSpanExporterBuilder.create(udpSpanExporter, resource).build();
       spanProcessors.push(
-        new AwsBatchUnsampledSpanProcessor(
-          new OTLPUdpSpanExporter(getXrayDaemonEndpoint(), FORMAT_OTEL_UNSAMPLED_TRACES_BINARY_PREFIX),
-          {
-            maxExportBatchSize: getSpanExportBatchSize(),
-          }
-        )
+        new AwsBatchUnsampledSpanProcessor(configuredExporter, {
+          maxExportBatchSize: getSpanExportBatchSize(),
+        })
       );
       diag.info('Enabled batch unsampled span processor for Lambda environment.');
     }