fix: emoji in image `alt` text will be replaced by `<svg>`

[n0099]

🐛 The bug

🛠️ To reproduce

https://stackblitz.com/edit/nuxt-starter-3hr14scv?file=components%2FOgImage%2FMyTemplate.vue

🌈 Expected behavior

Just render the image and ignore the alt text like what satori did.

ℹ️ Additional context

No response