patch 8.2.0103: using null object with execute() has strange effects

Problem:    Using null object with execute() has strange effects.
Solution:   Give an error message ofr Job and Channel.

src/version.c

@@ -742,6 +742,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    103,
 /**/
     102,
 /**/