Drop react-markdown node prop from rendered comment links

The custom `a` renderer spread react-markdown's internal `node` prop onto
the anchor, leaking node="[object Object]" into the DOM on every comment link.
Destructure it out.

src/components/student/lesson-comments.tsx

@@ -51,7 +51,8 @@ function CommentBody({ text }: { text: string }) {
       <ReactMarkdown
         rehypePlugins={[rehypeSanitize]}
         components={{
-          a: ({ ...props }) => <a {...props} target="_blank" rel="noopener noreferrer" />,
+          // eslint-disable-next-line @typescript-eslint/no-unused-vars -- отбрасываем служебный node от react-markdown, чтобы он не протекал в DOM
+          a: ({ node, ...props }) => <a {...props} target="_blank" rel="noopener noreferrer" />,
         }}
       >
         {text}