Need to build release artifact for an older GNU/Linux version

Hi,

I need to build my releases against GNU/Linux 2.6.32, for example:
This is what I need

```
$ cargo build --target x86_64-unknown-linux-gnu --release
$ file manta
manta: ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, for GNU/Linux 2.6.32, BuildID[sha1]=3bddb4eb2ebf10ab63469a165b6f7d8263ebdaf7, with debug_info, not stripped
```

The above is what I need which is building an artifact for an older glib version.

My problem is I am switching to cargo dist to manage my github cicd pipeline and I am under the impression that `cargo dist build --target="x86_64-unknown-linux-gnu" --tag=${{ github.ref_name }} --output-format=json ${{ matrix.dist-args }} > dist-manifest.json` is building the artifact for a more recent glib version.

```
$ file manta
$ manta: ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=3b3fdd0c6820f9e66bbb07fd73ad3e1e95900fbc, for GNU/Linux 3.2.0, with debug_info, not stripped
```

How can I tell `cargo dist` I want it to use GNU/Linux 2.6.32 instead of 3.2.0?

thank you very much

Start by examining the cargo dist build command and the GitHub CI pipeline described in the issue, then compare its GNU/Linux 3.2.0 output with the cargo build result targeting GNU/Linux 2.6.32. Done means the release artifact is built against the older glibc baseline and the file output confirms GNU/Linux 2.6.32 compatibility.

Written by the indexing model from the issue text.