display the word value as code again

src/content/chapter1_functions/lesson06_generic_functions/code.gleam

@@ -14,7 +14,7 @@ pub fn main() {
   io.debug(twice("Hello", exclaim))
 }
 
-// The name value refers to the same type multiple times
+// The name `value` refers to the same type multiple times
 fn twice(argument: value, function: fn(value) -> value) -> value {
   function(function(argument))
 }