Removed reference to pre-built Development docker image from the development dev_vpp_agent/README, since no prebuilt Dev docker images are available.
Removed reference to pre-built Development docker image from the development dev_vpp_agent/README, since no prebuilt Dev docker images are available.

ondrej-fabry/vpp-agent,VladoLavor/vpp-agent,VladoLavor/vpp-agent,VladoLavor/vpp-agent,ondrej-fabry/vpp-agent,ondrej-fabry/vpp-agent