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)
diff --git a/src/version.c b/src/version.c
index 8ae0a86..d99e18c 100644
--- a/src/version.c
+++ b/src/version.c
@@ -750,6 +750,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    3848,
+/**/
     3847,
 /**/
     3846,