Fix style guide for LightboxGallery component

ts/components/LightboxGallery.md

@@ -1,16 +1,58 @@
 ```js
 const noop = () => {};
 
-const items = [
-  { objectURL: 'https://placekitten.com/800/600', contentType: 'image/jpeg' },
-  { objectURL: 'https://placekitten.com/900/600', contentType: 'image/jpeg' },
-  { objectURL: 'https://placekitten.com/980/800', contentType: 'image/jpeg' },
-  { objectURL: 'https://placekitten.com/656/540', contentType: 'image/jpeg' },
-  { objectURL: 'https://placekitten.com/762/400', contentType: 'image/jpeg' },
-  { objectURL: 'https://placekitten.com/920/620', contentType: 'image/jpeg' },
+const messages = [
+  {
+    objectURL: 'https://placekitten.com/800/600',
+    attachments: [
+      {
+        contentType: 'image/jpeg',
+      },
+    ],
+  },
+  {
+    objectURL: 'https://placekitten.com/900/600',
+    attachments: [
+      {
+        contentType: 'image/jpeg',
+      },
+    ],
+  },
+  {
+    objectURL: 'https://placekitten.com/980/800',
+    attachments: [
+      {
+        contentType: 'image/jpeg',
+      },
+    ],
+  },
+  {
+    objectURL: 'https://placekitten.com/656/540',
+    attachments: [
+      {
+        contentType: 'image/jpeg',
+      },
+    ],
+  },
+  {
+    objectURL: 'https://placekitten.com/762/400',
+    attachments: [
+      {
+        contentType: 'image/jpeg',
+      },
+    ],
+  },
+  {
+    objectURL: 'https://placekitten.com/920/620',
+    attachments: [
+      {
+        contentType: 'image/jpeg',
+      },
+    ],
+  },
 ];
 
 <div style={{ position: 'relative', width: '100%', height: 500 }}>
-  <LightboxGallery items={items} onSave={noop} />
+  <LightboxGallery messages={messages} onSave={noop} />
 </div>;
 ```