public Optional<TopicBinding<SubscribeTrait>> getSubscribeBinding(ToShapeId operation) {
        return Optional.ofNullable(subscribeBindings.get(operation.toShapeId()));
    }
Gets the MQTT subscribe binding of an operation.

@param operation Operation that has MQTT bindings.
@return Returns the optionally found MQTT subscribe bindings.
smithy-mqtt-traits/src/main/java/software/amazon/smithy/mqtt/traits/ResolvedTopicIndex.java