remove dead code: ShaderDefs derive (bevyengine#3490)

# Objective

- remove some dead code and see if someone isn't happy about it


Co-authored-by: François <8672791+mockersf@users.noreply.github.com>

crates/bevy_derive/src/lib.rs

@@ -5,7 +5,6 @@ mod bevy_main;
 mod bytes;
 mod enum_variant_meta;
 mod modules;
-mod shader_defs;
 
 use bevy_macro_utils::{derive_label, BevyManifest};
 use proc_macro::TokenStream;
@@ -17,13 +16,6 @@ pub fn derive_bytes(input: TokenStream) -> TokenStream {
     bytes::derive_bytes(input)
 }
 
-/// Derives the ShaderDefs trait. Each field must implement ShaderDef or this will fail.
-/// You can ignore fields using `#[shader_defs(ignore)]`.
-#[proc_macro_derive(ShaderDefs, attributes(shader_def))]
-pub fn derive_shader_defs(input: TokenStream) -> TokenStream {
-    shader_defs::derive_shader_defs(input)
-}
-
 /// Generates a dynamic plugin entry point function for the given `Plugin` type.  
 #[proc_macro_derive(DynamicPlugin)]
 pub fn derive_dynamic_plugin(input: TokenStream) -> TokenStream {

crates/bevy_derive/src/modules.rs

@@ -1,3 +1,2 @@
 pub const BEVY_CORE: &str = "bevy_core";
-pub const BEVY_RENDER: &str = "bevy_render";
 pub const BEVY_UTILS: &str = "bevy_utils";