Few days ago GPG keys was updated. Please see post of @lukasz.mitka about this:
There was recently update for GPG keys in ROS repositories, you can change them with:
sudo apt-key adv --keyserver 'hkp://keyserver.ubuntu.com:80' --recv-key C1CF6E31E6BADE8868B172B4F42ED6FBAB17C654
sudo apt-key del 421C365BD9FF1F717815A3895523BAEEB01FA116
More details are explained on ROS discourse.
Note that everyone who use ROS have to execute this commands.