docker: use upstream repo for containerd

http://github.com/docker/containerd is archived and redirects to
https://github.com/docker-archive/containerd.

To make updates easier track the upstream repo which Docker uses.

pkgs/applications/virtualization/docker/default.nix

@@ -33,7 +33,7 @@ rec {
       name = "docker-containerd-${version}";
       inherit version;
       src = fetchFromGitHub {
-        owner = "docker";
+        owner = "containerd";
         repo = "containerd";
         rev = containerdRev;
         sha256 = containerdSha256;