Consistently guard restarts against concurrent auto updates (#21016)

packages/cli/src/utils/processUtils.test.ts

@@ -5,7 +5,11 @@
  */
 
 import { vi } from 'vitest';
-import { RELAUNCH_EXIT_CODE, relaunchApp } from './processUtils.js';
+import {
+  RELAUNCH_EXIT_CODE,
+  relaunchApp,
+  _resetRelaunchStateForTesting,
+} from './processUtils.js';
 import * as cleanup from './cleanup.js';
 import * as handleAutoUpdate from './handleAutoUpdate.js';
 
@@ -19,6 +23,10 @@ describe('processUtils', () => {
     .mockReturnValue(undefined as never);
   const runExitCleanup = vi.spyOn(cleanup, 'runExitCleanup');
 
+  beforeEach(() => {
+    _resetRelaunchStateForTesting();
+  });
+
   afterEach(() => vi.clearAllMocks());
 
   it('should wait for updates, run cleanup, and exit with the relaunch code', async () => {