[test] Clean timeout on completion

If the test are fast in theory the next set up can be started
and fail in the middle of waiting.

Bug: none
Change-Id: I642c5c8894651140bce53e949fbb8240b100a7ff
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/6252781
Reviewed-by: Danil Somsikov <[email protected]>
Commit-Queue: Nikolay Vitkov <[email protected]>

Author: Lightning00Blade

front_end/ui/visual_logging/Debugging.ts

@@ -674,7 +674,8 @@ export async function expectVeEvents(expectedEvents: TestLogEntry[]): Promise<vo
   const {promise, resolve: success, reject: fail} = Promise.withResolvers<void>();
   pendingEventExpectation = {expectedEvents, success, fail};
   checkPendingEventExpectation();
-  setTimeout(() => {
+
+  const timeout = setTimeout(() => {
     if (pendingEventExpectation?.missingEvents) {
       pendingEventExpectation.fail(new Error(
           'Missing VE Events: ' +
@@ -683,7 +684,10 @@ export async function expectVeEvents(expectedEvents: TestLogEntry[]): Promise<vo
               .join('\n')));
     }
   }, EVENT_EXPECTATION_TIMEOUT);
-  return promise;
+
+  return promise.finally(() => {
+    clearTimeout(timeout);
+  });
 }
 
 let numMatchedEvents = 0;