Log errors when loading textures from a gltf file (bevyengine#2260)

When loading a gltf, if there is an error loading textures, it is completely ignored.

This can happen for example when loading a file with `jpg` textures without the `jpeg` Bevy feature enabled.
This PR adds `warn` logs for the few cases that can happen when loading a texture.

Other possible fix would be to break on first error and returning, making the asset loading failed

crates/bevy_gltf/src/loader.rs

@@ -4,6 +4,7 @@ use bevy_asset::{
 };
 use bevy_core::Name;
 use bevy_ecs::world::World;
+use bevy_log::warn;
 use bevy_math::Mat4;
 use bevy_pbr::prelude::{PbrBundle, StandardMaterial};
 use bevy_render::{
@@ -49,7 +50,7 @@ pub enum GltfError {
     BufferFormatUnsupported,
     #[error("invalid image mime type: {0}")]
     InvalidImageMimeType(String),
-    #[error("{0}")]
+    #[error("You may need to add the feature for the file format: {0}")]
     ImageError(#[from] TextureError),
     #[error("failed to load an asset path: {0}")]
     AssetIoError(#[from] AssetIoError),
@@ -262,7 +263,12 @@ async fn load_gltf<'a, 'b>(
             });
         })
         .into_iter()
-        .filter_map(|result| result.ok())
+        .filter_map(|res| {
+            if let Err(err) = res.as_ref() {
+                warn!("Error loading GLTF texture: {}", err);
+            }
+            res.ok()
+        })
         .for_each(|(texture, label)| {
             load_context.set_labeled_asset(&label, LoadedAsset::new(texture));
         });