patch 8.0.0789: splitting terminal window has resizing problems

Problem:    When splitting a terminal window where the terminal follows the
            size of the window doesn't work.
Solution:   Use the size of the smallest window. (Yasuhiro Matsumoto, closes
            #1885)
diff --git a/src/version.c b/src/version.c
index 7d06669..83e8735 100644
--- a/src/version.c
+++ b/src/version.c
@@ -770,6 +770,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    789,
+/**/
     788,
 /**/
     787,