patch 8.2.4404: Vim9: some code not covered by tests

Problem:    Vim9: some code not covered by tests.
Solution:   Add a few specific test cases.

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    4404,
 /**/
     4403,
 /**/