Enables config test for prohibiting swap on app machines
Enables config test for prohibiting swap on app machines

Still permitting swap presence on Monitor hosts, since the first-run
Ansible config hasn't been updated to remove it there. Changes to the
Ansible config are tracked in #1620.

conorsch/securedrop,heartsucker/securedrop,ageis/securedrop,conorsch/securedrop,ageis/securedrop,micahflee/securedrop,heartsucker/securedrop,heartsucker/securedrop,ageis/securedrop,conorsch/securedrop,garrettr/securedrop,ehartsuyker/securedrop,garrettr/securedrop,heartsucker/securedrop,ageis/securedrop,heartsucker/securedrop,micahflee/securedrop,conorsch/securedrop,ehartsuyker/securedrop,conorsch/securedrop,ehartsuyker/securedrop,ehartsuyker/securedrop,micahflee/securedrop,garrettr/securedrop,ehartsuyker/securedrop,micahflee/securedrop,ehartsuyker/securedrop,garrettr/securedrop