AbilityState::ready and friends should take actions by reference, not value

[alice-i-cecile]

Which feature is frustrating to use or confusing?

        let ability_id = ability_loadout.get_id(slot).unwrap();
        let ability = ability_manifest.get(ability_id).unwrap();
        let is_ready = ability_state.ready(ability.clone());

Expectation

This should take the ability by reference; there's no need to do otherwise.