patch 8.1.0859: "%v" in 'errorformat' does handle multi-byte characters

Problem:    "%v" in 'errorformat' does handle multi-byte characters.
Solution:   Handle multi-byte characters. (Yegappan Lakshmanan, closes #3700)
diff --git a/src/version.c b/src/version.c
index 9422f84..ed4c1b5 100644
--- a/src/version.c
+++ b/src/version.c
@@ -784,6 +784,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    859,
+/**/
     858,
 /**/
     857,