Change agent-server.codechain.io to dashboard-server.codechain.io

[majecty]

We renamed agent -> dashboard-client and agent-server(agent-hub) -> dashboard-server. The domains are left as un changed. Let's change them.

Also, change the Corgi's URL: agent-server.corgi.codechain.io

[majecty]

I made dashboard-server.corgi.codechain.io domain and dashboard-server.codechain.io domain. Let's remove the original domains(agent-server.codechain.io and dashboard-server.codechain.io) few days later.