Support "cgroupns" docker parameter

[nervo]

Now that docker desktop 4.3.0+ uses cgroupv2 (see: https://docs.docker.com/desktop/mac/release-notes/#docker-desktop-430) we need to specify cgroupns to host in order to run systemd based containers.

[tbumke]

For everyone still waiting for this feature, there is a workaround available for Docker for Mac 4.3.0+ by switching back to now deprecated cgroups v1. See also docker/for-mac#6073.

[vician]

This is currently blocked by ansible-collections/community.docker#338 which is blocked by docker/docker-py#2930

[bngsudheer]

I have submitted a PR

[jdelStrother]

This was fixed in community.docker 3.0 - you can now set cgroupns_mode: host in the platform definition