yadm does not correctly identify host is WSL2

[G. Paul]

1) $lsb_release -rd
Description: Ubuntu 20.04.3 LTS
Release: 20.04

Running in WSL2 on Windows 10

2)$ apt-cache policy yadm
yadm:
  Installed: 2.3.0-2
  Candidate: 2.3.0-2
  Version table:
 *** 2.3.0-2 500
        500 http://archive.ubuntu.com/ubuntu focal/universe amd64 Packages
        100 /var/lib/dpkg/status

3) What you expected to happen:

Given the following files: "example##os.WSL" and "example##os.Linux",
and given that I am running ubuntu under WSL2:

When picking between alternate files `yadm alt` should choose "example##os.WSL"

4) What happened instead:

`yadm alt` chooses "example##os.Linux"

This bug in yadm was fixed in yadm 2.4
See: https://github.com/TheLocehiliosan/yadm/issues/196

Workaround: run `yadm config os.Local WSL` to manually set the local OS name