sequelize only migrate the first part of the configuration.

## What happens?
执行`npx sequelize db:migrate`。但只在config的第一个`database_development`中生成了`users`表，其他两个数据库没有成功生成`users`表。

```base
{
"development": {
"username": "root",
"password": null,
"database": "database_development",
"host": "127.0.0.1",
"dialect": "mysql"
},
"test": {
"username": "root",
"password": null,
"database": "database_test",
"host": "127.0.0.1",
"dialect": "mysql"
},
"production": {
"username": "root",
"password": null,
"database": "database_production",
"host": "127.0.0.1",
"dialect": "mysql"
}
}
```


## Mini Showcase Repository(REQUIRED)
> Provide a mini GitHub repository which can reproduce the issue.
> Use `npm init egg --type=simple bug` then upload to your GitHub

## How To Reproduce

**Steps to reproduce the behavior:**
1. 在`database/config.json`中自动生成的配置，
2. 在MySQL中分别创建了这3个数据库`database_development` `database_test` `database_production`，
3. 且在`database/migrations`中自动生成了一个关于`users`的文件，配置后。
4. 执行`npx sequelize db:migrate`。但只在配置的第一个`database_development`中生成了`users`表，配置中的其他两个数据库没有成功生成`users表`。

**Expected behavior**

当然是期望3个数据库都成功生成`users`表。

## Context
- **Node Version**: 16.13.1
- **Egg Version**: 2.15.1
- **Plugin Name**: egg-sequelize
- **Plugin Version**: 6.0.0
- **Platform**: win10 pro