This project scares me because it helps foster a bad practice -- keeping secrets in a repo. You really shouldn't be keeping secrets in the repo.
You should be using a secrets service that is designed for such a purpose, like Hashicorp's Vault[0], so that you never have to keep a secret in the code.
Perhaps it's an alternative practice/behavior rather than a "bad" practice?
It's a bad practice, because git makes keys practically irrevocable. It's not enough to rotate encryption keys, because the old ciphertexts are in the git history; you have to rotate the underlying secrets as well (people don't do this and shouldn't have to).
Don't store encrypted secrets in git if you can avoid it.
The problem is you need some repository to store this information and it's incredibly helpful to store the configuration along with the code.
If someone has access to a shared secret and then shouldn't you should assume the secret is now compromised and rotate it. Rotating the keys doesn't solve this problem.