IMPORTANT: Please do not create a Pull Request without creating an issue first.

Problem:

The dhcp-agent pod's init container is using the docker.io/library/busybox:latest image. The image is not packed in the ISO image we shipped, so it'll cause trouble when users enable the harvester-vm-dhcp-controller add-on in air-gapped Harvester clusters.

Solution:

Instead of using docker.io/library/busybox:latest to configure the dhcp-agent pod's IP address, use docker.io/rancher/harvester-vm-dhcp-agent:<tag> as the new image. Because of that, we need to add the iproute2 package into the agent image.

Related Issue:

harvester/harvester#6942

Test plan:

1. Install the harvester-vm-dhcp-controller experimental add-on
2. Enable the add-on
3. Create an IPPool object
4. Ensure the IPPool object's conditions are all good, especially the AgentReady one
5. Create a VM
6. Ensure the VM gets the IP address recorded in the corresponding VirtualMachineNetworkConfig object