Fixes: #9478 Issue link: https://github.com/spring-projects/spring-integration/issues/9478 Any `MessagingGatewaySupport` implementation does not register itself into a `SmartLifecycleRoleController` because they don't call `super.onInit()` of the `AbstractEndpoint` * Fix `MessagingGatewaySupport` for calling `super.onInit()` from its `onInit()` * Verify `SmartLifecycleRoleController` registration in the `KafkaInboundGatewayTests` * Remove out of use XML `group-id` attribute from Kafka channel adapter and move it to the `channel` XSD as the place where it is really used **Auto-cherry-pick to `6.3.x` & `6.2.x`**