add autocomplete to oh-my-zsh code example

Example: oh my zsh autocomplete

# clone repo for auto-suggestion and syntax-highlighting
git clone https://github.com/zsh-users/zsh-autosuggestions.git $ZSH_CUSTOM/plugins/zsh-autosuggestions
git clone https://github.com/zsh-users/zsh-syntax-highlighting.git $ZSH_CUSTOM/plugins/zsh-syntax-highlighting

# open config file 
nano ~/.zshrc

## add "zsh-autosuggestions zsh-syntax-highlighting" in plugins section