Mitigate a deprecation of `MappingJackson2MessageConverter` from Spring Framework `7.0`

[artembilan]

This is where we use it:

• ConfigurableCompositeMessageConverter
• WebSocketInboundChannelAdapter
• WebSocketOutboundMessageHandler
• StompInboundChannelAdapterWebSocketIntegrationTests

Has to be migrated to a new JacksonJsonMessageConverter.