docs: Improve incorrect example of using useScriptTriggerElement

[jelmerdemaat]

Improve incorrect example of useScriptTriggerElement so it includes the specifically named property el as such

❓ Type of change

• 📖 Documentation (updates to the documentation or readme)
• 🐞 Bug fix (a non-breaking change that fixes an issue)
• 👌 Enhancement (improving an existing functionality)
• ✨ New feature (a non-breaking change that adds functionality)
• 🧹 Chore (updates to the build process or auxiliary tools and libraries)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

This PR corrects a mistake in the documentation that incorrectly shows the possibility of providing the function useScriptTriggerElement with a property called somethingEl, while that should be called el.

[vercel]

@jelmerdemaat is attempting to deploy a commit to the Nuxt Team on Vercel.

A member of the Team first needs to authorize it.

[harlan-zw]

Thanks!