Apply suggestion from @Copilot

sumn2u · Copilot · web-flow · commit 44e547bf5ccd · 2025-12-01T07:22:56.000-05:00
Co-authored-by: Copilot &lt;175728472+Copilot@users.noreply.github.com&gt;
diff --git a/cn/strings/charAt.md b/cn/strings/charAt.md
@@ -32,7 +32,7 @@ function func() {
 func();
 
 //Output
-j
+J
 s
 
 //Example 2: 
