Provid a more friendly message when our svc validation returns an error

[advdv]

We do custom validation in the svc package that now returns errors like:

Using non-ascii characters results in shitty error: 
$ nerd job run --name=😝weirdname nerdalize/pythonapp:v3
error: Key: 'RunJobInput.Name' Error:Field validation for 'Name' failed on the 'printascii' tag

We want to make this more friendly