c1d29ab385
Fixes https://github.com/spring-projects/spring-integration/issues/3732 The `Mqttv5PahoMessageDrivenChannelAdapter` unconditionally tries to (un)subscribe to/from topics when the `mqqtClient` might not be initialized yet. * Add `mqqtClient` initialization check before adding or removing topic. Re-align logic with the `MqttPahoMessageDrivenChannelAdapter` **Cherry-pick to `5.5.x`**