Include more "ip" information in Agent supportbundle

[antoninbas]

At the moment, we include the output of the ip link, ip route and ip address commands.

Reference:

antrea/pkg/support/dump_others.go

Lines 62 to 76 in 4e74a6b

	func (d *agentDumper) dumpIPToolInfo(basedir string) error {
	dump := func(name string) error {
	output, err := d.executor.Command("ip", name).CombinedOutput()
	if err != nil {
	return fmt.Errorf("error when dumping %s: %w", name, err)
	}
	return writeFile(d.fs, filepath.Join(basedir, name), name, output)
	}
	for _, item := range []string{"route", "link", "address"} {
	if err := dump(item); err != nil {
	return err
	}
	}
	return nil
	}

When troubleshooting Egress SNAT issues, and in particular when EgressSeparateSubnet is used, this information is insufficient: we are missing IP rules (ip rules) and we need all the routes installed by Antrea (ip route show table all or something more specific?), not just the ones from the default route table.

Additionally, again for Egress, it would be nice to include the rp_filter configuration of created VLAN sub-interfaces. More generally, maybe we could include the relevant configurations (arp_ignore, rp_filter, arp_announce) of all relevant network interfaces.

cc @tnqn

[codeEvolveZenith345]

Hi @antoninbas
I would Like to work on it please assign it to me.