接入IAP的时候需要输入谷歌的开发者后台key
Unity2020之后有可能会提示：you are not authorized to set the license key
查阅相关内容后（https://forum.unity.com/threads/purchase-you-are-not-authorized-to-set-the-license-key-google-play.954261/）
Unity2020后不在Editor上面填写了，改成在Dashboard上输入
打开后输入即刻