How to prevent "Do you want to terminate running processes" window when shutting down? When I have running processes on my terminal and I try to shutdown Mac, I get this window:



I want all running processes to terminate automatically when I shut down my Mac without being prompted the window shown above. Is there a way to do that? 

I am using macOS Sierra 10.12.6.

Edit: My question is not about iTerm2 or closing tabs.
Terminal Preferences → Profiles, select the profile you're using (probably marked Default) in the sidebar on the left, then choose Shell. Under ‘Ask before closing:’, choose Never.