[kubernetes] decide what to do with /run/containerd

[errordeveloper]

In order to work around and issue with OCI whiteout files and kata's use of 9p filesystem, the tmpfs was used for containerd image store. There is plenty of RAM and it's a nice speed-up, but RAM could be used for something else instead. Additioanlly, at present we are using /run that is mounted by systemd, if we want to carry on relying on tmpfs, we should probably create a dedicated mountpoint and gain control of its size allocation.