Use improved traits of Slot data structure

Author: nazar-pc

crates/sc-consensus-subspace/src/slot_worker.rs

@@ -417,7 +417,7 @@ where
             // Ensure proof of time is valid according to parent block
             if !self.pot_verifier.is_output_valid(
                 pot_input,
-                Slot::from(u64::from(slot) - u64::from(parent_slot)),
+                slot - parent_slot,
                 proof_of_time,
                 parent_pot_parameters.next_parameters_change(),
             ) {

crates/sc-proof-of-time/src/source/gossip.rs

@@ -580,7 +580,7 @@ where
         match GossipProof::decode(&mut data) {
             Ok(proof) => {
                 let next_slot_input = self.state.next_slot_input(atomic::Ordering::Relaxed);
-                let current_slot = Slot::from(u64::from(next_slot_input.slot) - 1);
+                let current_slot = next_slot_input.slot - Slot::from(1);
 
                 if proof.slot < current_slot {
                     trace!(

crates/subspace-service/src/lib.rs

@@ -341,14 +341,14 @@ where
                     if quick_verification {
                         pot_verifier.try_is_output_valid(
                             pot_input,
-                            Slot::from(slot - u64::from(parent_slot)),
+                            Slot::from(slot) - parent_slot,
                             proof_of_time,
                             pot_parameters.next_parameters_change(),
                         )
                     } else {
                         pot_verifier.is_output_valid(
                             pot_input,
-                            Slot::from(slot - u64::from(parent_slot)),
+                            Slot::from(slot) - parent_slot,
                             proof_of_time,
                             pot_parameters.next_parameters_change(),
                         )