Upgrade to beancount 3.x

[hosiet]

Hi, thanks for the great project to ease fava deployment. I am wondering whether we can look into integrating beancount 3.x in the deployment, given that beancount 3.x and its fava support should be stable now. Thanks!

[wmader23]

To add on that. Would a PR to integrate beancount version 3 be welcome?

[dhr2333]

https://github.com/dhr2333/Beancount-Trans-Assets This project already supports the use of beancount v3.1.0 and Fava 1.30.1, you can refer to