remove dotenv from with-stripe-typescript (#15814)
remove dotenv from with-stripe-typescript (#15814)

removed the dotenv dependency in favor of Next.js environment support: #15225

The example seems to work with no other changes required
![Screenshot 2020-08-03 at 12 03 22 PM](https://user-images.githubusercontent.com/11258286/89152753-557d6480-d581-11ea-919c-4b89a6bec4b6.png)

flybayer/next.js,azukaru/next.js,zeit/next.js,zeit/next.js,zeit/next.js,JeromeFitz/next.js,azukaru/next.js,JeromeFitz/next.js,flybayer/next.js,flybayer/next.js,azukaru/next.js,JeromeFitz/next.js,JeromeFitz/next.js,azukaru/next.js,flybayer/next.js