Error when "sudo apt update"

Question

I was trying to run the command sudo apt update, but I'm getting the following error:

$ sudo apt update
    E: Malformed entry 1 in list file /etc/apt/sources.list.d/lutris.list (Suite)
    E: The list of sources could not be read.

How can I fix this?

I checked the file /etc/apt/sources.list.d/lutris.list and is a text file containing only the following line:

deb http://download.opensuse.org/repositories/home:/strycore/xUbuntu_17.10/

Thank you