document few more cli examples using docker in readme

[glimchb]

it took me a minute to make it work, so think it is helpful for people to have this info documented

$ docker run --rm -it --network=container:opi-evpn-bridge-opi-evpn-bridge-1 docker.io/namely/grpc-cli ls localhost:50151
grpc.reflection.v1.ServerReflection
grpc.reflection.v1alpha.ServerReflection
opi_api.network.evpn_gw.v1alpha1.BridgePortService
opi_api.network.evpn_gw.v1alpha1.LogicalBridgeService
opi_api.network.evpn_gw.v1alpha1.SviService
opi_api.network.evpn_gw.v1alpha1.VrfService

and

$ docker run --rm -it --network=container:opi-evpn-bridge-opi-evpn-bridge-1 docker.io/opiproject/godpu:main evpn list-vrfs --addr=localhost:50151
2023/09/13 17:00:21 VRF with
 name: //network.opiproject.org/vrfs/blue
 operation status: 0
 vni : 0
 vtep ip : addr:{af:IP_AF_INET v4_addr:167772162} len:32
 loopback ip: addr:{af:IP_AF_INET v4_addr:167772418} len:32
2023/09/13 17:00:21 VRF with
 name: //network.opiproject.org/vrfs/green
 operation status: 0
 vni : 100
 vtep ip : addr:{af:IP_AF_INET v4_addr:167772162} len:32
 loopback ip: addr:{af:IP_AF_INET v4_addr:167772674} len:32
2023/09/13 17:00:21 VRF with
 name: //network.opiproject.org/vrfs/yellow
 operation status: 0
 vni : 101
 vtep ip : addr:{af:IP_AF_INET v4_addr:167772162} len:32
 loopback ip: addr:{af:IP_AF_INET v4_addr:167772930} len:32

[glimchb]

added one example here c1f0da9