fix: validate messages recursively

feat: throw exception from testing helpers

chore: set current version to 3.6.0-beta.4

feat: forward exception from error policy to publish message factory

fix: fix UnboundSequence memory leak

chore: set current version to 3.6.0-beta.1

feat: update dependencies

fix: prevent ObjectDisposedException when reconnecting the MqttClient…

… after connection lost

chore: release v4.1.0-beta.2

fix: handle acknowledgement timeout (QoS>0) in MqttConsumer

If a the message processing takes longer than the allotted timeout for the acknowledge, the broker will resend the message. This prevented the message to be committed by the SkipPolicy, since the MqttConsumer assumed that concurrent consuming was not possible.