Layout example fix (#4463)

* Update forced-layout example

Enforce layout to an explicit block index to allow for other block types

* Update site/examples/forced-layout.tsx

* fix layout example to comply with linting rules

Co-authored-by: Lukas Murdock <lukas.murdock@gmail.com>

site/examples/forced-layout.tsx

@@ -32,13 +32,27 @@ const withLayout = editor => {
       }
 
       for (const [child, childPath] of Node.children(editor, path)) {
-        const type = childPath[0] === 0 ? 'title' : 'paragraph'
+        let type: string
-
+        const slateIndex = childPath[0]
+        const enforceType = type => {
           if (SlateElement.isElement(child) && child.type !== type) {
             const newProperties: Partial<SlateElement> = { type }
             Transforms.setNodes(editor, newProperties, { at: childPath })
           }
         }
+
+        switch (slateIndex) {
+          case 0:
+            type = 'title'
+            enforceType(type)
+            break
+          case 1:
+            type = 'paragraph'
+            enforceType(type)
+          default:
+            break
+        }
+      }
     }
 
     return normalizeNode([node, path])