refactor(test utils): replace sleep promise implementation with Nod…

…ejs timers (#414)

packages/bee-q/src/shared/test-utils/sleep.ts

@@ -1,7 +1 @@
-import { promisify } from 'util';
-
-/**
- * Delay function which returns a promise with setTimeout as callback function
- * @returns {void}
- */
-export const sleep = promisify(setTimeout);
+export { setTimeout as sleep } from 'timers/promises';