[Agent Observability] Enable HTTP instrumentation for Agent Observability (#215)

*Issue #, if available:*

*Description of changes:*


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Author: jj22ee

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

@@ -57,7 +57,7 @@ export function setAwsDefaultEnvironmentVariables() {
     if (!process.env.OTEL_NODE_ENABLED_INSTRUMENTATIONS) {
       // Assume users only need aws-sdk and aws-lambda instrumentations, as well as
       // instrumentations that are manually set-up outside of OpenTelemetry
-      process.env.OTEL_NODE_ENABLED_INSTRUMENTATIONS = 'aws-lambda,aws-sdk';
+      process.env.OTEL_NODE_ENABLED_INSTRUMENTATIONS = 'aws-lambda,aws-sdk,http';
     }
 
     // Set exporter defaults

aws-distro-opentelemetry-node-autoinstrumentation/test/register.test.ts

@@ -102,7 +102,7 @@ describe('Register', function () {
       expect(process.env.OTEL_INSTRUMENTATION_GENAI_CAPTURE_MESSAGE_CONTENT).toEqual('true');
       expect(process.env.OTEL_TRACES_SAMPLER).toEqual('parentbased_always_on');
       expect(process.env.OTEL_NODE_DISABLED_INSTRUMENTATIONS).toEqual('fs,dns');
-      expect(process.env.OTEL_NODE_ENABLED_INSTRUMENTATIONS).toEqual('aws-lambda,aws-sdk');
+      expect(process.env.OTEL_NODE_ENABLED_INSTRUMENTATIONS).toEqual('aws-lambda,aws-sdk,http');
       expect(process.env.OTEL_AWS_APPLICATION_SIGNALS_ENABLED).toEqual('false');
       expect(process.env.OTEL_EXPORTER_OTLP_TRACES_ENDPOINT).toEqual('https://xray.us-east-1.amazonaws.com/v1/traces');
       expect(process.env.OTEL_EXPORTER_OTLP_LOGS_ENDPOINT).toEqual('https://logs.us-east-1.amazonaws.com/v1/logs');