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The crate [`humantime`](https://crates.io/crates/humantime) appears to
be unmaintained. There's open PR in RustSec's advisory-db about this:
rustsec/advisory-db#2249

The crates [`clap`](https://crates.io/crates/clap) and
[`env_logger`](https://crates.io/crates/env_logger) have already made
the switch from `humantime` to [`jiff`](https://crates.io/crates/jiff):

 * clap-rs/clap#5944
 * rust-cli/env_logger#352

The `jiff` crate is already dependency on `cargo` via `gix` (albeit old
0.1 version, but that's probably fixed in [next gix
release](GitoxideLabs/gitoxide@3ae99a4)):

```
jiff v0.1.29
└── gix-date v0.9.3
    ├── gix v0.70.0
    │   └── cargo v0.88.0 (/Users/oherrala/rust/cargo)
```

This PR shouldn't have any functional change to cargo itself.