replace trailing whitespace with blackslash in README.md

As an alternative to the markdown trailing whitespace as a line
break, we use a trailing blackslash as a markdown line break.

2005/toledo/README.md

@@ -1,8 +1,8 @@
 # Best Game
 
-Oscar Toledo G.  
-Familia Toledo  
-Mexico  
+Oscar Toledo G.\
+Familia Toledo\
+Mexico\
 <https://nanochess.org>
 
 ## To build: