Apply suggestions from code review

Co-authored-by: Jean-Philippe Raynaud <[email protected]>

Author: curiecrypt

mithril-stm/src/membership_commitment/merkle_tree/leaf.rs

@@ -1,6 +1,7 @@
-use serde::{Deserialize, Serialize};
 use std::cmp::Ordering;
 
+use serde::{Deserialize, Serialize};
+
 use crate::{
     MerkleTreeError, Stake, StmResult, VerificationKey, signature_scheme::BlsVerificationKey,
 };

mithril-stm/src/protocol/aggregate_signature/signature.rs

@@ -1,7 +1,8 @@
+use std::{collections::HashMap, fmt::Display, hash::Hash};
+
 use anyhow::anyhow;
 use blake2::digest::{Digest, FixedOutput};
 use serde::{Deserialize, Serialize};
-use std::{collections::HashMap, fmt::Display, hash::Hash};
 
 use super::AggregateVerificationKey;
 use crate::{

mithril-stm/src/protocol/key_registration.rs

@@ -1,11 +1,12 @@
 //! Key registration functionality.
-use anyhow::anyhow;
-use blake2::digest::{Digest, FixedOutput};
 use std::{
     collections::{HashMap, hash_map::Entry},
     sync::Arc,
 };
 
+use anyhow::anyhow;
+use blake2::digest::{Digest, FixedOutput};
+
 use crate::{
     RegisterError, Stake, StmResult,
     membership_commitment::{MerkleTree, MerkleTreeLeaf},

mithril-stm/src/protocol/single_signature/signature.rs

@@ -1,11 +1,12 @@
-use anyhow::{Context, anyhow};
-use blake2::digest::{Digest, FixedOutput};
-use serde::{Deserialize, Serialize};
 use std::{
     cmp::Ordering,
     hash::{Hash, Hasher},
 };
 
+use anyhow::{Context, anyhow};
+use blake2::digest::{Digest, FixedOutput};
+use serde::{Deserialize, Serialize};
+
 use crate::{
     AggregateVerificationKey, Index, Parameters, SignatureError, Stake, StmResult, VerificationKey,
     is_lottery_won, signature_scheme::BlsSignature,