fix(dashboard): pass content as children to ReactMarkdown

Self-closing <ReactMarkdown /> renders nothing — need children.

小橘 <xiaoju@shazhou.work>

packages/workflow-dashboard/src/components/markdown.tsx

@@ -100,8 +100,9 @@ export function Markdown({ content }: { content: string }) {
               </blockquote>
             );
           },
-        }}
+        }}>
-      />
+        {content}
+      </ReactMarkdown>
     </div>
   );
 }