Revert "touch: Ship Lomiri Polkit Agent"
It turns out, removing LSS-security-privacy's built-in Polkit agent and rely on Lomiri one regress the user experience significantly. So let's revert both LSS-security-privacy's agent removal and this commit for now.
This reverts commit 9882432e.
Bug: ubports/development/core/lomiri-system-settings-security-privacy#7 (closed)