Fix middleware-general test for Turbopack (vercel#56211)

This test failed for Turbopack because of the rename from `i18n` to `__i18n` to not use that config. Turbopack does checking of config options to ensure it doesn't run when an option is not implemented, so that caused the test run to bail out.

Author: timneutkens

test/e2e/middleware-general/app/next.config.js

@@ -18,47 +18,72 @@ describe('Middleware Runtime', () => {
   let next: NextInstance
 
   const setup = ({ i18n }: { i18n: boolean }) => {
-    let nextConfigContent = ''
-    const nextConfigPath = join(__dirname, '../app/next.config.js')
-
     afterAll(async () => {
       await next.destroy()
-
-      if (nextConfigContent) {
-        await fs.writeFile(nextConfigPath, nextConfigContent)
-      }
     })
     beforeAll(async () => {
-      if (!i18n) {
-        nextConfigContent = await fs.readFile(nextConfigPath, 'utf8')
-        await fs.writeFile(
-          nextConfigPath,
-          nextConfigContent.replace('i18n', '__i18n')
-        )
-      }
       next = await createNext({
         files: {
-          'next.config.js': new FileRef(
-            join(__dirname, '../app/next.config.js')
-          ),
           'middleware.js': new FileRef(join(__dirname, '../app/middleware.js')),
           pages: new FileRef(join(__dirname, '../app/pages')),
           'shared-package': new FileRef(
             join(__dirname, '../app/node_modules/shared-package')
           ),
         },
+        nextConfig: {
+          experimental: {
+            webpackBuildWorker: true,
+          },
+          ...(i18n
+            ? {
+                i18n: {
+                  locales: ['en', 'fr', 'nl'],
+                  defaultLocale: 'en',
+                },
+              }
+            : {}),
+          async redirects() {
+            return [
+              {
+                source: '/redirect-1',
+                destination: '/somewhere/else',
+                permanent: false,
+              },
+            ]
+          },
+          async rewrites() {
+            return [
+              {
+                source: '/rewrite-1',
+                destination: '/ssr-page?from=config',
+              },
+              {
+                source: '/rewrite-2',
+                destination: '/about/a?from=next-config',
+              },
+              {
+                source: '/sha',
+                destination: '/shallow',
+              },
+              {
+                source: '/rewrite-3',
+                destination: '/blog/middleware-rewrite?hello=config',
+              },
+            ]
+          },
+        },
         packageJson: {
           scripts: {
             setup: `cp -r ./shared-package ./node_modules`,
-            build: 'yarn setup && next build',
-            dev: `yarn setup && next ${
+            build: 'pnpm run setup && next build',
+            dev: `pnpm run setup && next ${
               shouldRunTurboDevTest() ? 'dev --turbo' : 'dev'
             }`,
             start: 'next start',
           },
         },
-        startCommand: (global as any).isNextDev ? 'yarn dev' : 'yarn start',
-        buildCommand: 'yarn build',
+        startCommand: (global as any).isNextDev ? 'pnpm dev' : 'pnpm start',
+        buildCommand: 'pnpm run build',
         env: {
           ANOTHER_MIDDLEWARE_TEST: 'asdf2',
           STRING_ENV_VAR: 'asdf3',