bug: cargo run ends in an error

[tac0turtle]

running cargo run after modifying main.rs like mentioned in the readme results in an error

[info] Updating cosmos/cosmos-sdk submodule...
fatal: cannot change to '../cosmos-sdk-go': No such file or directory
thread 'main' panicked at '"git" exited with error code: 128', proto-build/src/main.rs:144:27
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

any hints on how to solve this. I can dive into the repo, but wanted to open an issue either way