zig: error: version '.2.17' in target triple 'x86_64-unknown-linux-gnu.2.17' is invalid

I try to use cargo-zigbuild to build [helix](https://github.com/helix-editor/helix) by the following command
```
> helix/helix-term
cargo zigbuild --target x86_64-unknown-linux-gnu.2.17 --release
```

I get
```
warning: helix-term@25.7.1: zig: error: version '.2.17' in target triple 'x86_64-unknown-linux-gnu.2.17' is invalid
```

The resulting binary has no problem though.