patch 8.2.3334: Vim9: not enough tests run with Vim9

Problem:    Vim9: not enough tests run with Vim9.
Solution:   Run a few more tests in Vim9 script and :def function. Fix
            islocked().  Fix error for locking local variable.

src/version.c

@@ -755,6 +755,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    3334,
 /**/
     3333,
 /**/