docs: update code-block (#1974)

Author: VoloDziu

docs/content/docs/foundations/document-structure.mdx

@@ -72,7 +72,6 @@ type CustomInlineContent = {
   content: StyledText[] | undefined;
   props: Record<string, boolean | number | string>;
 };
-```
 
 type InlineContent = Link | StyledText | CustomInlineContent;