duplicate code block creation when not set hljs language

[richex-cn]

TuSimple/naive-ui version (版本)

2.23.1

Vue version (Vue 版本)

3.2.26

Browser and its version (浏览器及其版本)

Chrome(96.0.4664.110)

System and its version (系统及其版本)

Windows 10

Node version (Node 版本)

Reappearance link (重现链接)

https://codesandbox.io/s/naive-ui-code-issue-duyz0

Reappearance steps (重现步骤)

// html
<n-code :code="code" />

// script
const code = ref('Hello')
setTimeout(() => {
  code.value = 'Hello World'
}, 1000)

Expected results (期望的结果)

Update content instead of duplicate creation

Actual results (实际的结果)

Each update of responsive data creates a code block

Remarks (补充说明)