Investigate use of `ssh-agent` for exploitation

# Spike
## Objective
See last comment on #2589.
It may be possible for us to use `ssh-agent` for exploitation. [This](https://rabexc.org/posts/using-ssh-agent) is a good read to understand what `ssh-agent` does. Since it saves keys, could we use this without ever having access to the keys? Look into how we can do this using paramiko.

## Scope
Figure out if we can use `ssh-agent` for exploitation.
Time boxed: 1.25d

## Output
An issue and a prototype if it can be used. An explanation if it can't.