`AsBindGroup` derive example error

The [`AsBindGroup` derive example](https://docs.rs/bevy/latest/bevy/render/render_resource/trait.AsBindGroup.html#deriving) has 5 bindings but the corresponding WGSL code only has 4. I suspect this is not intended (or I didn't understand the example).

Start with the AsBindGroup derive example in the linked docs.rs documentation and compare its listed bindings with the corresponding WGSL code. Done means the example's Rust and WGSL binding counts and declarations agree; no repository file or test is named in the issue.

Written by the indexing model from the issue text.