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.
diff --git a/src/version.c b/src/version.c
index 4e37402..d903192 100644
--- a/src/version.c
+++ b/src/version.c
@@ -756,6 +756,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    3334,
+/**/
     3333,
 /**/
     3332,