patch 8.2.3841: Vim9: outdated TODO items, disabled tests that work

Problem:    Vim9: outdated TODO items, disabled tests that work.
Solution:   Remove TODO items, run tests that work now.  Check that a dict
            item isn't locked.

src/version.c

@@ -749,6 +749,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    3841,
 /**/
     3840,
 /**/