make LocalCallExecutor public (#7528)

substrate/client/service/src/lib.rs

@@ -80,6 +80,7 @@ pub use sc_tracing::TracingReceiver;
 pub use task_manager::SpawnTaskHandle;
 pub use task_manager::TaskManager;
 pub use sp_consensus::import_queue::ImportQueue;
+pub use self::client::LocalCallExecutor;
 use sc_client_api::{blockchain::HeaderBackend, BlockchainEvents};
 
 const DEFAULT_PROTOCOL_ID: &str = "sup";