没有引入对应的语言，引入对应的语言就好了，主要问题还是在webpack打包的时候没有把对应的代码打进去
import 'highlight.js/styles/stackoverflow-light.css'
import hljs from 'highlight.js/lib/core';
import javascript from 'highlight.js/lib/languages/javascript';
import hljsVuePlugin from "@highlightjs/vue-plugin";
hljs.registerLanguage('javascript', javascript);
const app = createApp(App)
app.use(hljsVuePlugin)
app.mount('#app')
