Make extract_text2d_sprite public (#21104)

# Objective

Make `extract_text2d_sprite` `pub` again.

This was made private during the `bevy_sprite_render` migration. Doesn't
look like this was done intentionally, there's no mention of it in the
migration guides.

Author: ickshonpe

crates/bevy_sprite_render/src/lib.rs

@@ -45,7 +45,7 @@ use bevy_render::{
 use bevy_sprite::Sprite;
 
 #[cfg(feature = "bevy_text")]
-use crate::text2d::extract_text2d_sprite;
+pub use crate::text2d::extract_text2d_sprite;
 
 /// Adds support for 2D sprite rendering.
 #[derive(Default)]