Add CustomErrorHandler and use it

Ignore benign 'Bad Request: message to be replied not found' Telegram
error while logging other errors

src/bots_manager/mod.rs

@@ -1,6 +1,7 @@
 pub mod axum_server;
 pub mod bot_manager_client;
 pub mod closable_sender;
+pub mod custom_error_handler;
 pub mod internal;
 pub mod utils;