fix(node-integration-tests): fix flaky kafkajs test by making transaction order independent

The test was flaky because the producer and consumer transactions
could arrive in either order, but the test asserted them in a fixed
sequence. Now both transactions are collected and assertions are
performed after both have been received, regardless of arrival order.

Fixes #20121

Co-Authored-By: Claude <noreply@anthropic.com>

Agent-Logs-Url: https://github.com/getsentry/sentry-javascript/sessions/0bc166af-c93a-42a6-a762-dae244893e2b

Co-authored-by: Lms24 <8420481+Lms24@users.noreply.github.com>

Author: Copilot

dev-packages/node-integration-tests/suites/tracing/kafkajs/test.ts

@@ -1,3 +1,4 @@
+import type { TransactionEvent } from '@sentry/core';
 import { afterAll, describe, expect } from 'vitest';
 import { cleanupChildProcesses, createEsmAndCjsTests } from '../../../utils/runner';
 
@@ -8,16 +9,32 @@ describe('kafkajs', () => {
 
   createEsmAndCjsTests(__dirname, 'scenario.mjs', 'instrument.mjs', (createRunner, test) => {
     test('traces producers and consumers', { timeout: 60_000 }, async () => {
+      // The producer and consumer transactions can arrive in any order,
+      // so we collect them and assert after both have been received.
+      const receivedTransactions: TransactionEvent[] = [];
+
       await createRunner()
         .withDockerCompose({
           workingDirectory: [__dirname],
           readyMatches: ['9092'],
         })
         .expect({
-          transaction: {
-            transaction: 'send test-topic',
-            contexts: {
-              trace: expect.objectContaining({
+          transaction: (transaction: TransactionEvent) => {
+            receivedTransactions.push(transaction);
+          },
+        })
+        .expect({
+          transaction: (transaction: TransactionEvent) => {
+            receivedTransactions.push(transaction);
+
+            const producer = receivedTransactions.find(t => t.transaction === 'send test-topic');
+            const consumer = receivedTransactions.find(t => t.transaction === 'process test-topic');
+
+            expect(producer).toBeDefined();
+            expect(consumer).toBeDefined();
+
+            expect(producer!.contexts?.trace).toMatchObject(
+              expect.objectContaining({
                 op: 'message',
                 status: 'ok',
                 data: expect.objectContaining({
@@ -28,14 +45,10 @@ describe('kafkajs', () => {
                   'sentry.origin': 'auto.kafkajs.otel.producer',
                 }),
               }),
-            },
-          },
-        })
-        .expect({
-          transaction: {
-            transaction: 'process test-topic',
-            contexts: {
-              trace: expect.objectContaining({
+            );
+
+            expect(consumer!.contexts?.trace).toMatchObject(
+              expect.objectContaining({
                 op: 'message',
                 status: 'ok',
                 data: expect.objectContaining({
@@ -46,7 +59,7 @@ describe('kafkajs', () => {
                   'sentry.origin': 'auto.kafkajs.otel.consumer',
                 }),
               }),
-            },
+            );
           },
         })
         .start()