Update to zbus 5.x

https://github.com/dbus2/zbus/releases/tag/zbus-5.0.0

Now requires `pub` on uses of `#[proxy]` if the generated types should
be `pub`.

bluez/src/agent_manager1.rs

@@ -23,7 +23,7 @@ use zbus::proxy;
 	default_service = "org.bluez",
 	default_path = "/org/bluez"
 )]
-trait AgentManager1 {
+pub trait AgentManager1 {
 	/// RegisterAgent method
 	fn register_agent(
 		&self,