Reformat imports to a consistent style for imports

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

banks-server/src/banks_server.rs

@@ -1,5 +1,3 @@
-use solana_sdk::feature_set::FeatureSet;
-
 use {
     bincode::{deserialize, serialize},
     futures::{future, prelude::stream::StreamExt},
@@ -11,6 +9,7 @@ use {
         account::Account,
         clock::Slot,
         commitment_config::CommitmentLevel,
+        feature_set::FeatureSet,
         fee_calculator::FeeCalculator,
         hash::Hash,
         message::{Message, SanitizedMessage},

banks-server/src/rpc_banks_service.rs

@@ -103,8 +103,7 @@ impl RpcBanksService {
 
 #[cfg(test)]
 mod tests {
-    use super::*;
-    use solana_runtime::bank::Bank;
+    use {super::*, solana_runtime::bank::Bank};
 
     #[test]
     fn test_rpc_banks_server_exit() {