Tutorial mistakes

Hey :). Don't know where else to post this so...

Found 2 mistakes in this tutorial:

https://docs.graphene-python.org/projects/django/en/latest/tutorial-plain/

Where it says: "Now sync your database for the first time:"
There is no manage.py in that directory. One must go back one directory. So, `cd ..` first, and then execute the `python manage.py` migrate command.

Where it says: "Don’t forget to create & run migrations:"
This will fail because in `class IngredientsConfig(AppConfig): ` we have `name = 'ingredients'`. The name is wrong. It should be `name = 'cookbook.ingredients'`

从 docs.graphene-python.org/projects/django/en/latest/tutorial-plain/ 的教程开始，并在仓库中找到其源文件。确认数据库迁移命令所在的目录和 IngredientsConfig 名称，然后更新教程，并确认这两个步骤都能按文档说明正常工作。

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