patch 8.2.4083: Vim9: no test for "vim9script autoload' using script variable

Problem:    Vim9: no test for "vim9script autoload' and using script variable
            in the same script.
Solution:   Add a simple test.  Fix uncovered problem.

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    4083,
 /**/
     4082,
 /**/