Set validity by index for Utf8Array

[Arty-Maly]

I am curious if there is a better way to set a specific index to valid/invalid in a Utf8Array?

For PrimitiveArray for example I can do apply_validity But I don't think there is a method for Utf8Array. What would be an idiomatic way to invalidate an element in an Utf8Array?

[jorgecarleitao]

I think it would be a good idea to create one in Utf8Array, exactly for the use-case you are looking for!

Would you like to create a PR on it, or would you like me to do it?

[Arty-Maly]

I can create it, since I actually need this functionality.