Multus v3.9.3 has `--multus-master-cni-file-name` flag to specify the
name of a primary CNI config file.
https://github.com/k8snetworkplumbingwg/multus-cni/blob/v3.9.3/images/entrypoint.sh#L22
In Multus v4.0.2, the thin plugin has the flag defined, but it is not
read and so does not have effect.
This pull request fixes the problem by making the thin plugin correctly
handles `--multus-master-cni-file-name` flag.
Fixes#1226
Signed-off-by: Hidehito Yabuuchi <hyab@preferred.jp>
This commit changes thin container base image to distroless
to simplify container image. It replace old shell script entrypoint
to golang implementation and implement multus installer (i.e. copy).