test: move NODE_ENV assignment to vitest config

Per vitest-dev/vitest#5084 (comment)

Author: haoqunjiang

playground/vitestGlobalSetup.ts

@@ -9,10 +9,6 @@ const DIR = path.join(os.tmpdir(), 'vitest_playwright_global_setup')
 let browserServer: BrowserServer | undefined
 
 export async function setup(): Promise<void> {
-  process.env.NODE_ENV = process.env.VITE_TEST_BUILD
-    ? 'production'
-    : 'development'
-
   browserServer = await chromium.launchServer({
     headless: !process.env.VITE_DEBUG_SERVE,
     args: process.env.CI

vitest.config.e2e.ts

@@ -3,6 +3,10 @@ import { defineConfig } from 'vitest/config'
 
 const timeout = process.env.CI ? 50000 : 30000
 
+process.env.NODE_ENV = process.env.VITE_TEST_BUILD
+  ? 'production'
+  : 'development'
+
 export default defineConfig({
   resolve: {
     alias: {