patch 8.1.1606: on a narrow screen ":hi" output is confusing

Problem:    On a narrow screen ":hi" output is confusing.
Solution:   Insert a space between highlight group name and "xxx". (Masato
            Nishihaga, closes #4599)
diff --git a/src/version.c b/src/version.c
index 53c3c66..aa0b8be 100644
--- a/src/version.c
+++ b/src/version.c
@@ -778,6 +778,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1606,
+/**/
     1605,
 /**/
     1604,