patch 8.2.4031: crash in xterm with only two lines

Problem:    Crash in xterm with only two lines. (Dominique Pellé)
Solution:   Only perform xterm compatibility test if possible. (closes #9488)
diff --git a/src/version.c b/src/version.c
index 5658467..cc9d81e 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    4031,
+/**/
     4030,
 /**/
     4029,