Remove statement about supporting CNI plugin (#8594)
Remove statement about supporting CNI plugin (#8594)

* Remove statement about supporting CNI plugin

* Update install-cni-plugin.md

londoncalling/docker.github.io,docker/docker.github.io,londoncalling/docker.github.io,thaJeztah/docker.github.io,docker/docker.github.io,thaJeztah/docker.github.io,thaJeztah/docker.github.io,londoncalling/docker.github.io,thaJeztah/docker.github.io,thaJeztah/docker.github.io,londoncalling/docker.github.io,docker/docker.github.io,londoncalling/docker.github.io,docker/docker.github.io,docker/docker.github.io