Fix another link in thanks-for-fixes.md

thanks-for-fixes.md

@@ -12,7 +12,7 @@ We call out the extensive contributions of [Cody Boone
 Ferguson](https://www.ioccc.org/winners.html#Cody_Boone_Ferguson) who is
 responsible for many of the improvements including many, many **very complicated
 bug fixes** such as [2001/anonymous](2001/anonymous/README.md) and
-[2004/burley](2004/burley/burley.c), making entries not require
+[2004/burley](2004/burley/README.md), making entries not require
 `-traditional-cpp` (which are **very complicated fixes**), fixing entries to
 compile with clang, fixing entries to work with macOS (some of which are **very
 complicated** such as [1998/schweikh1](1998/schweikh1/README.md)), fixing code