View principals on a host certificate

Using the `step` CLI you can see which principals exist on a host certificate.

The quickest way to view a host certificate is as follows

# Manual command will show you the identity to reference (reference)
step ssh list

#Show the encrypted cert and identity (roughly the same as `ssh-add -L`)
step ssh list --raw

# Option 1: Copy the encrypted cert string and reference/pipe it to the following:
step ssh inspect [encrypted cert string]

# Option 2: everything in one command. NC==1 returns the first key in the array.
step ssh list $(ssh-add -L | awk '{print $3} NC==1') --raw | step ssh inspect