test(replay): make handleNetworkBreadcrumbs flush robust to await depth

waitForReplayEventBuffer hardcoded "one Promise.resolve() per await in the util
functions", so it silently coupled the test to the enrichment chain's exact
await count. That made a behavior-neutral lint fix (dropping a redundant
`return await` in _getResponseText) look like a data-loss regression.

Flush microtasks in a bounded loop instead, so the test no longer depends on
the implementation's await depth. _getResponseText keeps the rule-compliant
`return response.text()`.

Author: logaretm

packages/replay-internal/test/unit/coreHandlers/handleNetworkBreadcrumbs.test.ts

@@ -21,12 +21,12 @@ import { BASE_TIMESTAMP } from '../..';
 import { setupReplayContainer } from '../../utils/setupReplayContainer';
 
 async function waitForReplayEventBuffer() {
-  // Need one Promise.resolve() per await in the util functions
-  await Promise.resolve();
-  await Promise.resolve();
-  await Promise.resolve();
-  await Promise.resolve();
-  await Promise.resolve();
+  // Flush pending microtasks so the async network-breadcrumb enrichment settles into the buffer.
+  // Looping a fixed number of times (rather than one `Promise.resolve()` per await in the impl)
+  // keeps this robust to the enrichment chain's exact await depth.
+  for (let i = 0; i < 10; i++) {
+    await Promise.resolve();
+  }
 }
 
 const LARGE_BODY = 'a'.repeat(NETWORK_BODY_MAX_SIZE + 1);