edit the /etc/sudoers file and add this for your user (in the user privilege section - note without the % sign)
myuser ALL=(ALL) NOPASSWD: ALL
log off and login again.
PS: Your user will be allowed to execute without password. Hopefully you have disabled ssh access into lxd container for that user (or root) and dont use that username on erpnext. You can ssh into host and then bash into the container.