[libcxx] Fix a comment link for the unicode NBSP char. NFC. (#139692)

diff --git a/libcxx/src/locale.cpp b/libcxx/src/locale.cpp
index 9ea59a3..b3ec2895 100644
--- a/libcxx/src/locale.cpp
+++ b/libcxx/src/locale.cpp
@@ -3957,7 +3957,7 @@
 }
 
 static bool is_non_breaking_space(const char* ptr) {
-  // https://www.fileformat.info/info/unicode/char/0a/index.htm
+  // https://www.fileformat.info/info/unicode/char/a0/index.htm
   return ptr[0] == '\xc2' && ptr[1] == '\xa0';
 }
 #endif // _LIBCPP_HAS_WIDE_CHARACTERS