Issue Description:
When using the Firebase Client SDK with Jest and firebase emulators:exec, Jest fails to exit cleanly without the --forceExit flag, even when deleteApp() and terminate() are called in globalTeardown. This necessitates the use of --forceExit, which is undesirable as it can mask other potential issues.

Steps to Reproduce:

1. Set up a Jest test environment using Firebase Client SDK (e.g., for Firestore).
2. Run tests using firebase emulators:exec "jest".
3. Implement jest.globalTeardown.js with:

   const { deleteApp } = require('firebase/app');
   const { terminate } = require('firebase/firestore');
   const { app, db } = require('./src/firebase'); // Assuming app and db are exported
   
   module.exports = async () => {
     if (app) { await deleteApp(app); }
     if (db) { await terminate(db); }
   };

Observed Behavior:

• deleteApp(app) and terminate(db) are called successfully.
• why-is-node-running (if used in globalTeardown) reports 0 handle(s) keeping the process running.
• Jest issues a warning: "Jest did not exit one second after the test run has completed."
• There is a noticeable delay between Jest completing its tests and firebase emulators:exec initiating emulator shutdown.
• Using --forceExit in the Jest command makes Jest exit and suppresses the warning.

Expected Behavior:
The Firebase client library should provide teardown mechanisms (deleteApp, terminate, or others if necessary) that allow Jest to exit cleanly and promptly on its own, without requiring --forceExit. The Node.js process should terminate naturally after all Firebase resources are released.

Request:
Please provide guidance on how to tear down the Firebase SDK in a test environment, without requiring the test framework to forcefully exiting the process.