Reformat imports to a consistent style for imports

rustfmt.toml configuration:
  imports_granularity = "One"
  group_imports = "One"

runtime/tests/accounts.rs

@@ -1,20 +1,26 @@
-use log::*;
-use rand::{thread_rng, Rng};
-use rayon::prelude::*;
-use solana_runtime::{
-    accounts_db::{AccountsDb, LoadHint},
-    ancestors::Ancestors,
+use {
+    log::*,
+    rand::{thread_rng, Rng},
+    rayon::prelude::*,
+    solana_runtime::{
+        accounts_db::{AccountsDb, LoadHint},
+        ancestors::Ancestors,
+    },
+    solana_sdk::{
+        account::{AccountSharedData, ReadableAccount, WritableAccount},
+        clock::Slot,
+        genesis_config::ClusterType,
+        pubkey::Pubkey,
+    },
+    std::{
+        collections::HashSet,
+        sync::{
+            atomic::{AtomicBool, Ordering},
+            Arc,
+        },
+        time::Instant,
+    },
 };
-use solana_sdk::genesis_config::ClusterType;
-use solana_sdk::{
-    account::{AccountSharedData, ReadableAccount, WritableAccount},
-    clock::Slot,
-    pubkey::Pubkey,
-};
-use std::collections::HashSet;
-use std::sync::atomic::{AtomicBool, Ordering};
-use std::sync::Arc;
-use std::time::Instant;
 
 #[test]
 fn test_shrink_and_clean() {

runtime/tests/bank.rs

@@ -1,6 +1,8 @@
-use solana_runtime::bank::Bank;
-use solana_sdk::{genesis_config::create_genesis_config, hash::hash};
-use std::{sync::Arc, thread::Builder};
+use {
+    solana_runtime::bank::Bank,
+    solana_sdk::{genesis_config::create_genesis_config, hash::hash},
+    std::{sync::Arc, thread::Builder},
+};
 
 #[test]
 fn test_race_register_tick_freeze() {

runtime/tests/stake.rs

@@ -1,28 +1,30 @@
 #![allow(clippy::integer_arithmetic)]
-use solana_runtime::{
-    bank::Bank,
-    bank_client::BankClient,
-    genesis_utils::{create_genesis_config_with_leader, GenesisConfigInfo},
-};
-use solana_sdk::{
-    account::from_account,
-    account_utils::StateMut,
-    client::SyncClient,
-    message::Message,
-    pubkey::Pubkey,
-    signature::{Keypair, Signer},
-    stake::{
-        self, instruction as stake_instruction,
-        state::{Authorized, Lockup, StakeState},
+use {
+    solana_runtime::{
+        bank::Bank,
+        bank_client::BankClient,
+        genesis_utils::{create_genesis_config_with_leader, GenesisConfigInfo},
     },
-    sysvar::{self, stake_history::StakeHistory},
+    solana_sdk::{
+        account::from_account,
+        account_utils::StateMut,
+        client::SyncClient,
+        message::Message,
+        pubkey::Pubkey,
+        signature::{Keypair, Signer},
+        stake::{
+            self, instruction as stake_instruction,
+            state::{Authorized, Lockup, StakeState},
+        },
+        sysvar::{self, stake_history::StakeHistory},
+    },
+    solana_stake_program::stake_state,
+    solana_vote_program::{
+        vote_instruction,
+        vote_state::{Vote, VoteInit, VoteState, VoteStateVersions},
+    },
+    std::sync::Arc,
 };
-use solana_stake_program::stake_state;
-use solana_vote_program::{
-    vote_instruction,
-    vote_state::{Vote, VoteInit, VoteState, VoteStateVersions},
-};
-use std::sync::Arc;
 
 fn next_epoch(bank: &Arc<Bank>) -> Arc<Bank> {
     bank.squash();