patch 8.2.0469: Vim9: no error for missing ] after list

Problem:    Vim9: no error for missing ] after list.
Solution:   Add error message. Add more tests.
diff --git a/src/testdir/test_lambda.vim b/src/testdir/test_lambda.vim
index 7fdfb87..bc3d5ac 100644
--- a/src/testdir/test_lambda.vim
+++ b/src/testdir/test_lambda.vim
@@ -62,7 +62,7 @@
 function Test_lambda_fails()
   call assert_equal(3, {a, b -> a + b}(1, 2))
   call assert_fails('echo {a, a -> a + a}(1, 2)', 'E853:')
-  call assert_fails('echo {a, b -> a + b)}(1, 2)', 'E15:')
+  call assert_fails('echo {a, b -> a + b)}(1, 2)', 'E451:')
   echo assert_fails('echo 10->{a -> a + 2}', 'E107:')
 endfunc