refactor(test-utils): remove unused codes

packages/test-utils/src/server.ts

@@ -55,9 +55,6 @@ export async function stopServer () {
   if (ctx.serverProcess) {
     await ctx.serverProcess.kill()
   }
-  if (ctx.listener) {
-    await ctx.listener.close()
-  }
 }
 
 export function fetch (path: string, options?: any) {

packages/test-utils/src/types.ts

@@ -1,7 +1,6 @@
 import type { Nuxt, NuxtConfig } from '@nuxt/schema'
 import type { ExecaChildProcess } from 'execa'
 import type { Browser, LaunchOptions } from 'playwright'
-import type { Listener } from 'listhen'
 
 export type TestRunner = 'vitest' | 'jest'
 
@@ -32,7 +31,6 @@ export interface TestContext {
   browser?: Browser
   url?: string
   serverProcess?: ExecaChildProcess
-  listener?: Listener
 }
 
 export interface TestHooks {