Then probably the download of the ravenhearst mod didn't work (which should happen in line 2 of the code posted by vitamin, the line beginning with "git clone")
Probably your ubuntu doesn't have "git" installed. Lets improve the code:
sudo apt-get update
sudo apt-get install git
cd /tmp
git clone https://github.com/JaxTeller718/MainVersion/ ravenhearst
cd /tmp/ravenhearst
cp -rf $(ls -A) "$HOME/.steam/steam/steamapps/common/7 Days To Die/"
The first line should ask for your password, the second should tell you that it will install git and a few other packages needed by git and ask you if it thats ok. Answer with "y"
The fourth line (starting with "git clone") will tell you something like "Receiving objects: 1% ..." and depending on your internet connection will take quite a while for the 1% to get to 100%
After that you should see a directory /tmp/ravenhearst and there should be a few directories in it, among others a data and mod directory. The last line will copy all files into your 7days steam directory.