Create `gf` CLI

- it'll be similar to the `gh` cli
- but for now it'll be only used for authentication
  - so the current issue is we have to manually setup the git credential manager, otherwise we have to submit the PAT everytime we push or pull

- gh cli uses `gh auth git-credential`
- Source: [From GitHub CLI](https://github.com/cli/cli/blob/51dfeeaa72a04d2476a4a4036bf528b9af441106/pkg/cmd/auth/auth.go#L29)