Beta version of cargo (as a library) is broken by gix

### Current behavior 😯

Building of some packages that depend on gix are broken

See also #2541

### Expected behavior 🤔

Semver is followed, allowing packages to be used.

### Git behavior

N/A

### Steps to reproduce 🕹

```console
$ cargo new gix-reproducer
$ cd gix-reproducer
$ cargo add --git https://github.com/rust-lang/cargo.git --branch rust-1.96.0 cargo
$ cargo check
```