patch 8.1.0479: failure when setting 'varsofttabstop' to end in a comma

Problem:    Failure when setting 'varsofttabstop' to end in a comma. (Ralf
            Schandl)
Solution:   Reject value with trailing command.  Add test for invalid values
            (closes #3544)

src/version.c

@@ -792,6 +792,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    479,
 /**/
     478,
 /**/