fix library/std/src/sys_common/wtf8.rs

Co-authored-by: GrigorenkoPV <[email protected]>

Author: HTGAzureX1212

library/std/src/sys_common/wtf8.rs

@@ -438,7 +438,7 @@ impl Wtf8Buf {
     ///
     /// This does not copy the data (but may overwrite parts of it in place).
     ///
-    /// Surrogates are replaced with `"\u{FFFD}"` (the replacement character “ ”)
+    /// Surrogates are replaced with `"\u{FFFD}"` (the replacement character “�”)
     pub fn into_string_lossy(mut self) -> String {
         // Fast path: If we already have UTF-8, we can return it immediately.
         if self.is_known_utf8 {