I would like to manually set my ssh keys from a bash script provided in user data and disable the first time login password change request when logging with my ssh keys. Is this possible?

Here's what I'm doing so far:

#!/bin/bash

root_ssh_key="ssh-rss ..."

ssh_port=22
sshd_config="/etc/ssh/sshd_config"
sudo_user="dev"
sudo_user_home="/home/${sudo_user}"
sudo_user_ssh_key="ssh-rss ..."



# ########################
# updates

setup_updates() {

  echo "Running updates..."

  # get updates and install
  sudo apt-get update
  sudo apt-get dist-upgrade -y

}



# ########################
# user account

setup_account() {

  echo "Configuring user account..."

  # add the specified '$sudo_user'
  sudo adduser $sudo_user --disabled-password --gecos "" 

  # add '$sudo_user' to the sudo group
  sudo gpasswd -a $sudo_user sudo

  # add sudo permissions
  echo "$sudo_user ALL=(ALL) NOPASSWD:ALL" >> /etc/sudoers

  #
  # ssh access
  #

  ssh_folder=${sudo_user_home}/.ssh

  # create .ssh folder restrict permissions
  sudo mkdir -p -v $ssh_folder
  sudo chmod 700 $ssh_folder

  authorized_keys_file=${ssh_folder}/authorized_keys

  # create an authorized_keys's file
  sudo touch $authorized_keys_file

  # write the ssh keys to the user's authorized_keys file and restrict permissions
  echo $sudo_user_ssh_key > $authorized_keys_file
  sudo chmod 600 $authorized_keys_file

  # set $sudo_user as the owner of the folder
  sudo chown -R ${sudo_user}:sudo $ssh_folder

  # set port and disable authentication with passwords
  sudo sed -i -e "/^Port/s/^.*$/Port ${ssh_port}/" $sshd_config
  sudo sed -i -e '/^PasswordAuthentication/s/^.*$/PasswordAuthentication no/' $sshd_config
  sudo sed -i -e '/^PermitRootLogin/s/^.*$/PermitRootLogin without-password/' $sshd_config

  # allow root and $sudo_user to connect
  sudo echo -e "\nAllowUsers root $sudo_user" >> $sshd_config

  # restart
  sudo service ssh restart

  # set root ssh keys
  echo $root_ssh_key > "/root/.ssh/authorized_keys"

}



# ########################
# setup firewall
#

setup_firewall() {

  echo "Setting up ufw..."

  # defaults
  sudo ufw default deny incoming
  sudo ufw default allow outgoing

  # exceptions
  sudo ufw allow ${ssh_port}/tcp
  sudo ufw allow http
  sudo ufw allow https

  # start on boot
  sed -i -e '/^ENABLED/s/^.*$/ENABLED=yes/' /etc/ufw/ufw.conf

  # enable
  sudo ufw enable

}



# ########################
# main
#

main() {

  echo "Initializing droplet as $USER..."

  # check if user is root
  if [ "$UID" -ne 0 ] ; then
    echo "Must be root to run this script."
    exit 1
  fi  

  # setup_updates
  setup_account
  setup_firewall

  echo "Droplet initialized."
  echo "Rebooting..."

  sudo shutdown -r now

}


main

I'm able to immediately login with my dev account. But I would like to prevent that first time password change request for the root. How can I do this without providing my root ssh key outside of this script?