upgrade Ubuntu from wsl to wsl2

PS C:\Users\alex> wsl -l -v NAME STATE VERSION
* Ubuntu Running 1
docker-desktop-data Running 2
docker-desktop Running 2
Ubuntu-20.04 Stopped 2
PS C:\Users\alex> wsl --set-version Ubuntu 2Conversion in progress, this may take a few minutes...
For information on key differences with WSL 2 please visit https://aka.ms/wsl2
Conversion complete.
PS C:\Users\alex> wsl -l -v NAME STATE VERSION
* Ubuntu Stopped 2
docker-desktop-data Running 2
docker-desktop Running 2
Ubuntu-20.04 Stopped 2
PS C:\Users\alex>

Reset WSL password

C:\Users\alex>ubuntu config --default-user root

C:\Users\alex>ubuntu.exe
root@DESKTOP-GN4RPTT:~# whoami
root

root@DESKTOP-GN4RPTT:~# tail -3 /etc/passwd
sshd:x:109:65534::/run/sshd:/usr/sbin/nologin
pollinate:x:110:1::/var/cache/pollinate:/bin/false
alex:x:1000:1000:,,,:/home/alex:/bin/bash
root@DESKTOP-GN4RPTT:~# passwd alex
Enter new UNIX password:
Retype new UNIX password:
passwd: password updated successfully
root@DESKTOP-GN4RPTT:~# exit
logout

C:\Users\alex>ubuntu config --default-user alex