[MC-76387] Books load coloured unicode characters as black

This is based on: ~~MC-41270~~
To test this you need the texture pack provided there.

When you type on of these characters like:



in the chat or use it in a tellraw command (/tellraw @p {text:""}) you can see the character like it normally looks: ■ ( Warning: This is NOT the actual character)
But in the book it just looks like a black square (■)

In comparison:

Book

/give @a written_book 1 0 {pages:["{\"text\":\"\",\"extra\":[{\"text\":\"\"}]}"],title:Book,author:TellrawGenerator}

Tellraw

/tellraw @p {text:""}