"docker-containerd-shim": executable file not found in $PATH: unknown

We had a similar error in our Jenkins pipeline. Reinstalling docker with a stable channel fixed it.

$ sudo add-apt-repository \
   "deb [arch=amd64] https://download.docker.com/linux/ubuntu \
   $(lsb_release -cs) \
   stable"

(https://docs.docker.com/install/linux/docker-ce/ubuntu/)

So we assume it's a nightly / test build problem. (don't remember which channel we had before)