[RAC Select]Allow placeholder to be `ReactNode`

[Austaras]

Provide a general summary of the feature here

Title. There doesn't seem to be any reason to limit it to string.

🤔 Expected Behavior?

Make it ReactNode

😯 Current Behavior

It only allows string

💁 Possible Solution

No response

🔦 Context

I'd like to pass some rich text to placeholder.

💻 Examples

No response

🧢 Your Company/Team

No response

🕷 Tracking Issue

No response

[reidbarber]

On one hand placeholder is restricted to string for native input elements, but I think for the Select use case, we should probably allow custom placeholders if we allow custom values to be rendered. It is a bit weird that it wouldn't match other RAC components though.

[Austaras]

I tried as unknown as string but it somehow doesn't work. I guess it's not a type definition only issue.