How do you customize the --version flag?

The documentation [mentions](https://github.com/dotnet/command-line-api/blob/main/docs/Features-overview.md#version-option) that `System.CommandLine` supports the `--version` flag out of the box but it doesn't show how to override its default value, and I cannot find any method on the RootCommand class to set it.

Side suggestion 1: Change the default value from `1.0.0` to `0.1.0`. When an app follows semantic versioning its first release is usually very far from 1.0.

Side suggestion 2: Enable [GitHub Discussions](https://github.blog/2021-08-17-github-discussions-out-of-beta/) on the repo so that the community can ask ~obnoxious~ newbie questions like this one there and declutter the Issues section.