Stray pixels of the sky are visible through chiseled bookshelves when using custom model

You can wrongly see stray pixels of the sky through solid blocks if they have a custom model.

Reproduction Steps:

• Download and enable the 3D Chiseled Bookshelves resourcepack from https://vanillatweaks.net/picker/resource-packs/

• Join this minecraft world: New World (27).zip

• You should see the stray pixels everywhere

Expected Results:

• There would be no stray pixels of the sky visible

Observed Results:

• Stray pixels of the sky appear through solid blocks