详情描述：
执行 php flarum migrate出错！
Migrating extension: fof-upload
Nothing to migrate.
Migrating extension: itnt-uitab
Nothing to migrate.
Migrating extension: fof-best-answer
In Connection.php line 664:
SQLSTATE[23000]: Integrity constraint violation: 1022 Can't write; duplicate key in table '#sql
-43cb_e3a9' (SQL: alter table `discussions` add constraint `discussions_best_answer_post_id_for
eign` foreign key (`best_answer_post_id`) references `posts` (`id`) on delete set null)
In PDOStatement.php line 129:
SQLSTATE[23000]: Integrity constraint violation: 1022 Can't write; duplicate key in table '#sql
-43cb_e3a9'
In PDOStatement.php line 127:
SQLSTATE[23000]: Integrity constraint violation: 1022 Can't write; duplicate key in table '#sql
-43cb_e3a9'
migrate [-h|--help] [-q|--quiet] [-v|vv|vvv|--verbose] [-V|--version] [--ansi] [--no-ansi] [-n|--no-interaction] [--] <command>