fix: fix stroke-linejoin

Author: xiaoyu2er

apps/docs/src/mdx/Icon.tsx

@@ -77,7 +77,7 @@ export const BackButton = () => {
     <svg
       className="text-current"
       height="16"
-      stroke-linejoin="round"
+      strokeLinejoin="round"
       viewBox="0 0 16 16"
       width="16"
       style={{ color: 'currentcolor' }}