Refresh the plugins pin alongside multus v4.3.1 (#1131), as the
cni-plugins-installer.yaml comment asks. SHA256 cross-checked against
upstream's cni-plugins-linux-amd64-v1.9.1.tgz.sha256 asset. The tarball
still ships macvlan, static, host-local and dhcp.
Image only: CI builds cni-plugins:<date>. The DaemonSet tag bump follows
in a separate PR once the image exists.
Refs: REN-722
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>