Investigate if we can remove the need to use Jenkins cli over remoting

What

Currently the installer uses the remoting flag when running commands via the jenkins cli. We should not do this if possible and investigate if we can instead use the ssh user.

Why

The remoting flag is deprecated and has potential risks from a security perspective. See https://jenkins.io/doc/book/managing/cli/#remoting-connection-mode and https://jenkins.io/doc/book/managing/cli

How

We already know the user and htey have to upload their ssh key as is so we should be able to allow us to specify the ssh connection at this point.