a new table with FK will not create stats_meta by ddl event

[hawkingrei]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

create table t_parent (id int primary key);
create table t_child (id int primary key, pid int, foreign key (pid) references t_parent(id) on delete cascade on update cascade);
show stats_meta;

2. What did you expect to see? (Required)

t_parent and t_child

3. What did you see instead (Required)

only t_parent

4. What is your TiDB version? (Required)

master