patch 8.2.3848: cannot use reduce() for a string

Problem:    Cannot use reduce() for a string.
Solution:   Make reduce() work with a string. (Naruhiko Nishino, closes #9366)

src/version.c

@@ -749,6 +749,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    3848,
 /**/
     3847,
 /**/