patch 8.2.3148: Vim9: function arg type check does not handle base offset

Problem:    Vim9: function arg type check does not handle base offset.
Solution:   Take the base offset into account when checking builtin function
            argument types.
diff --git a/src/testdir/test_vim9_builtin.vim b/src/testdir/test_vim9_builtin.vim
index e26c2c0..a17d92a 100644
--- a/src/testdir/test_vim9_builtin.vim
+++ b/src/testdir/test_vim9_builtin.vim
@@ -2305,6 +2305,8 @@
 
 def Test_win_execute()
   assert_equal("\n" .. winnr(), win_execute(win_getid(), 'echo winnr()'))
+  assert_equal("\n" .. winnr(), 'echo winnr()'->win_execute(win_getid()))
+  assert_equal("\n" .. winnr(), win_execute(win_getid(), 'echo winnr()', 'silent'))
   assert_equal('', win_execute(342343, 'echo winnr()'))
 enddef