networking: Remove redundant imports
networking: Remove redundant imports

Networking uses Cockpit's ListingTable, which already has these imports.

martinpitt/cockpit,cockpit-project/cockpit,cockpit-project/cockpit,martinpitt/cockpit,cockpit-project/cockpit,martinpitt/cockpit,cockpit-project/cockpit,martinpitt/cockpit,cockpit-project/cockpit,martinpitt/cockpit