Yuru Shao

Results 2 issues of Yuru Shao

Couldn't build the stripe SDK with XCode 11.4/11.5 due to "Incompatible block pointer types", also see https://github.com/tipsi/tipsi-stripe/issues/632. Should upgrade stripe SDK version: https://github.com/tipsi/tipsi-stripe/issues/632#issuecomment-607672078

1. default mypy python version to 3.10 2. remove py37 from black target version list