Review behavior changes of net-ssh 5.x and make adjustments as needed

[claudijd]

We recently got a report of a behavior change in net-ssh 5.x builds, released a few days ago, this bug is to investigate what changed that prevents NullVerifiers and any other behavior to see what we need to fix up.

I also increased out integration coverage to better detect this, although, I wish it would just run daily and let me know when/if it breaks. That or publishing a gemfile.lock in the repo and periodically revisiting to bump deps and update. Though, I'm a fan of living on the edge and dealing with small bumps rather than delayed big bumps with multiple thigns to fix.

[NullbutC00L]

Fix:
go to file ssh_scan.gemspec and change on line 35 the net-ssh version to '5.0.2' go ahead and save it

next go to lib/ssh_scan/ and edit scan_engine.rb on line 99 and change the line to :paranoid => false

you may need to go back a couple of folders to the ssh_scan root and run: gem build ssh_scan.gemspec

[claudijd]

@fmjgomes I made a PR for these changes, please have a look if you can for review (#441)