Hello,
To make the SUDO_PASSWORD_HASH work, you have to generate it.
For example:
openssl passwd -6 -salt RANDOM_STRING_USED_AS_SALT YOURPASSWORD
(-6 for sha512, -5 for sha256)
You will get a string in this format: $type$salt$hashed (as documented)
If you use docker-compose, don't forget to put $$ instead of $ in the environment variable: $$6$$SALT$$HASHEDPASSWORD
The password will be set in /etc/shadow.