debian-iptables(bullseye): Drop package installations from backports
debian-iptables(bullseye): Drop package installations from backports

iptables and ebtables are at sufficiently recent versions in bullseye
that installing from bullseye-backports should not be necessary.

Signed-off-by: Stephen Augustus <0beec7b5ea3f0fdbc95d0dd47f3c5bc275da8a33@auggie.dev>

kubernetes/release,kubernetes/release