patch 8.0.0703: illegal memory access with empty :doau command

Problem:    Illegal memory access with empty :doau command.
Solution:   Check the event for being out of range. (James McCoy)
diff --git a/src/version.c b/src/version.c
index 70de1d4..d494900 100644
--- a/src/version.c
+++ b/src/version.c
@@ -765,6 +765,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    703,
+/**/
     702,
 /**/
     701,