Quic Connection Cache (#23598)

Add a connection cache to allow add modules that send data to get or create connections (e.g. for quic) associated with a certain SocketAddr

client/src/lib.rs

@@ -4,6 +4,7 @@ extern crate serde_derive;
 
 pub mod blockhash_query;
 pub mod client_error;
+pub mod connection_cache;
 pub(crate) mod http_sender;
 pub(crate) mod mock_sender;
 pub mod nonblocking;