wsl install docs need updating to handle appx format

[maphew]

Describe the bug

The docs for installing YunoHost on WSL need updating (https://yunohost.org/en/install/hardware:wsl). The debian package downloaded from the command shown uses .appx microsoft store format and does not immediately include install.tar.gz needed for the next step in the docs, which blocks carrying out the install.

Workaround

1. Unpack the downloaded debian.zip
2. Rename .appx .zip >> unpack the new zip with right architecture (which is always x64 for win10?)
   Expand-Archive DistroLauncher-Appx_1.12.2.0_x64.zip -Destination-Path .\x
3. Run wsl import with path to x temp folder:
   wsl --import yunohost .\yunohost .\debian\x\install.tar.gz --version 2

adapted from https://dev.to/vpraharsha03/installing-msft-store-wsl-distros-to-a-custom-location-4m00

[maphew]

There are other things in the wsl install doc to be updated also:

• Legacy iptables doesn't seem to be available anymore
• Genie: the mirror specified for translinux does not exist (https://wsl-translinux.arkane-systems.net/)
• Win11 and WSL 0.67.6 and later have systemd already (https://github.com/arkane-systems/genie#wsl-now-has-native-systemd-support), though maybe it will need some extra help to be used like other systemd systems (https://github.com/arkane-systems/bottle-imp)