Set default for ansible_ssh_extra_args
Set default for ansible_ssh_extra_args

ansible-base in 2.10.16 changed how SSH option defaults worked breaking
this. Just ensuring it has a proper default instead of undefined solves
the issue.

roots/bedrock-ansible,roots/bedrock-ansible,pressbooks/trellis,roots/trellis,roots/trellis,pressbooks/trellis