test: re-implement promises.setInterval() test robustly

By using events, we can make sure the call to `controller.abort()`
doesn't happen before the next iteration starts.

Fixes: nodejs#37226

test/parallel/test-timers-promisified.js

@@ -10,6 +10,7 @@ const child_process = require('child_process');
 const { NodeEventTarget } = require('internal/event_target');
 
 const timerPromises = require('timers/promises');
+const EventEmitter = require('events');
 
 /* eslint-disable no-restricted-syntax */
 
@@ -350,16 +351,21 @@ process.on('multipleResolves', common.mustNotCall());
   }
 
   {
-    // Check that if we abort when we have some callbacks left,
+    // Check that if we abort when we have some unresolved callbacks,
     // we actually call them.
     const controller = new AbortController();
+    const myEvent = new EventEmitter();
     const { signal } = controller;
     const delay = 10;
     let totalIterations = 0;
     const timeoutLoop = runInterval(async (iterationNumber) => {
+      myEvent.emit('myevent');
+      // The call to abort() will typically happen while we're awaiting here.
+      await setTimeout(delay);
       if (iterationNumber === 2) {
-        await setTimeout(delay * 2);
-        controller.abort();
+        myEvent.once('myevent', () => {
+          controller.abort();
+        });
       }
       if (iterationNumber > totalIterations) {
         totalIterations = iterationNumber;