patch 8.2.4932: not easy to filter the output of maplist()

Problem:    Not easy to filter the output of maplist().
Solution:   Add mode_bits to the dictionary. (Ernie Rael, closes #10356)
diff --git a/src/testdir/test_vim9_builtin.vim b/src/testdir/test_vim9_builtin.vim
index 2c4e9ae..3405d9e 100644
--- a/src/testdir/test_vim9_builtin.vim
+++ b/src/testdir/test_vim9_builtin.vim
@@ -2464,7 +2464,8 @@
         scriptversion: 999999,
         rhs: 'bar',
         buffer: 0,
-        abbr: 0})
+        abbr: 0,
+        mode_bits: 0x47})
   unmap foo
   v9.CheckDefAndScriptFailure(['maparg(1)'], ['E1013: Argument 1: type mismatch, expected string but got number', 'E1174: String required for argument 1'])
   v9.CheckDefAndScriptFailure(['maparg("a", 2)'], ['E1013: Argument 2: type mismatch, expected string but got number', 'E1174: String required for argument 2'])