feat: add vouch

[TobiWo]

Summary

This PR will add vouch as vc client.

[barnabasbusa]

Looks like this pr wasn't actually tested with vouch yet :D

  Caused by: An error occurred waiting for all TCP and UDP ports to be open for service 'vc-1-besu-grandine-vouch' with private IP '172.16.0.21'; this is usually due to a misconfiguration in the service itself, so here are the logs:
  == SERVICE 'vc-1-besu-grandine-vouch' LOGS ===================================
  unknown flag: --beacon-node
  Usage of /app/vouch:
        --base-dir string                base directory for configuration files
        --beacon-node-address string     Address on which to contact the beacon node
        --log-file string                redirect log output to a file
        --log-level string               minimum level of messsages to log (default "info")
        --profile-address string         Address on which to run Go profile server
        --proposer-config-check string   show the proposer configuration for the given public key and exit
        --tracing-address string         Address to which to send tracing data
        --version                        show Vouch version and exit
  unknown flag: --beacon-node
  
  == FINISHED SERVICE 'vc-1-besu-grandine-vouch' LOGS ===================================
  Caused by: An error occurred while waiting for all TCP and UDP ports to be open
  Caused by: Unsuccessful ports check for IP '172.16.0.21' and port spec '{privatePortSpec:0x4000b5f590}', even after '240' retries with '500' milliseconds in between retries. Timeout '2m0s' has been reached
  Caused by: An error occurred while calling network address '172.16.0.21:8080' with port protocol 'TCP' and using time out '200ms'
  Caused by: dial tcp 172.16.0.21:8080: connect: no route to host

[TobiWo]

Hi @barnabasbusa , sorry didn't had the time to work on it further. However, a friend is still working on it although he didn't commit anything yet. I wonder why it wasn't a draft already. I'm pretty sure I set it as draft. Anyway, if you are fine with it we can keep it open.

[barnabasbusa]

Happy to review when its ready.