1.3.0 has some breaking changes

[KoditkarVedant]

I had released the 1.3.0 version of Notion.Net client which has the critical bug as it implements the some breaking API changes introduced in Notion API version 2021-08-16.

For those who have upgraded their package to 1.3.0 can do any of the below so you will not face issues when reading the response of Append block children API.

• Downgrade to 1.2.0
• Pass the API version as 2021-08-16 in client option when initializing the client

We are planning to create a separate branch for 2021-05-13 version of API's and solve any bug fixes and will release 2.0.0 version of package which will support the changes introduced in 2021-08-16 API version.