Encapsulate log::Level so counter macro users don't need to use it

runtime/src/accounts.rs

@@ -2,7 +2,7 @@ use crate::bank::{BankError, Result};
 use crate::runtime::has_duplicates;
 use bincode::serialize;
 use hashbrown::{HashMap, HashSet};
-use log::{debug, Level};
+use log::debug;
 use solana_metrics::counter::Counter;
 use solana_sdk::account::Account;
 use solana_sdk::hash::{hash, Hash};