Merge #2036

2036: Fix examples using ron spritesheets r=azriel91 a=0x6273

## Description

#2023 changed the spritesheet struct, which broke some of the examples that tried to load the old struct from ron files. This pr updates those ron files to use the new `Sprites` struct. 

## Modifications

- update some example ron files to use the new `Sprites` struct

## PR Checklist

By placing an x in the boxes I certify that I have:

- [x] Updated the content of the book if this PR would make the book outdated.
- [x] Added a changelog entry if this will impact users, or modified more than 5 lines of Rust that wasn't a doc comment.
- [x] Added unit tests for new code added in this PR.
- [x] Acknowledged that by making this pull request I release this code under an MIT/Apache 2.0 dual licensing scheme.

If this modified or created any rs files:

- [x] Ran `cargo +stable fmt --all`
- [x] Ran `cargo clippy --all --features "empty"`
- [x] Ran `cargo test --all --features "empty"`

Co-authored-by: 0x40 <0x40@keemail.me>

examples/assets/texture/Background.ron

@@ -1,17 +1,13 @@
 /*!
-    @import /amethyst_rendy/src/sprite/mod.rs#SpriteList
-    SpriteList
+    @import /amethyst_rendy/src/sprite/mod.rs#Sprites
+    Sprites
 */
 
-(
-  texture_width: 512,
-  texture_height: 512,
-  sprites: [
-    (
-      x: 0,
-      y: 0,
-      width: 512,
-      height: 512,
-    ),
-  ],
-)
+#![enable(implicit_some)]
+
+Grid((
+    texture_width: 512,
+    texture_height: 512,
+    columns: 1,
+    rows: 1,
+))

examples/assets/texture/Circle_Spritesheet.ron

@@ -1,23 +1,13 @@
 /*!
-    @import /amethyst_rendy/src/sprite/mod.rs#SpriteList
-    SpriteList
+    @import /amethyst_rendy/src/sprite/mod.rs#Sprites
+    Sprites
 */
 
-(
-  texture_width: 128,
-  texture_height: 64,
-  sprites: [
-    (
-      x: 0,
-      y: 0,
-      width: 64,
-      height: 64,
-    ),
-    (
-      x: 64,
-      y: 0,
-      width: 64,
-      height: 64,
-    ),
-  ],
-)
+#![enable(implicit_some)]
+
+Grid((
+    texture_width: 128,
+    texture_height: 64,
+    columns: 2,
+    rows: 1,
+))