Tedge Agent terminates mqtt connection when it tries to parse the incorrect payload

[Ruadhri17]

Describe the bug
Tedge Agent closes mqtt connection when there was a problem while parsing the payload. It applies to any tedge agent's topic. After closing the mqtt channel it cannot get any more messages and requires restart.

To Reproduce

1. Start thin-edge.io and all its components
2. Send mqtt message with incorrect payload to one of tedge agent's topics using tedge mqtt pub, e.g. tedge mqtt pub 'tedge/commands/req/software/list' '{"ids": "100"}'.
3. You can check that tedge-agent got error message using systemctl status tedge-agent.service.
4. Try to send the same message again.
5. Check tedge-agent status again, it will show message: INFO mqtt_channel::connection: MQTT connection closed

Expected behavior
Tedge-agent should continue running MQTT session when getting errors unless it is problem with MQTT actor.

Log Output

2023-09-06T14:24:55.178009719Z  INFO mqtt_channel::connection: MQTT connection established    
2023-09-06T14:24:55.205492916Z  INFO plugin_sm::plugin_manager: Plugin activated: /etc/tedge/sm-plugins/apt
2023-09-06T14:24:55.205552216Z  INFO plugin_sm::plugin_manager: Default plugin type: Not configured
2023-09-06T14:24:59.516701347Z ERROR Runtime: Actor TedgeOperationConverter-5 has finished unsuccessfully: ActorError(FromSerdeJson(Error("unknown field `ids`, expected `id`", line: 1, column: 6)))    
2023-09-06T14:25:00.194768512Z ERROR Runtime: Actor MQTT-2 has finished unsuccessfully: ChannelError(SendError(SendError { kind: Disconnected }))    
2023-09-06T14:25:00.194861412Z  INFO mqtt_channel::connection: MQTT connection closed   

Environment (please complete the following information):

• OS [incl. version] : Debian 11
• Hardware [incl. revision]:
• System-Architecture [e.g. result of "uname -a"] : Linux 57954d635aa0 5.15.90.1-microsoft-standard-WSL2 #1 SMP Fri Jan 27 02:56:13 UTC 2023 x86_64 GNU/Linux
• thin-edge.io version [e.g. 0.1.0]: 0.12.1~221+gd7c6e05

Additional context

We had similar issue in c8y-log-plugin: #2161 so it might be similar problem here.

[gligorisaev]

QA has thoroughly checked the feature and here are the results:

• Test for ticket exists in the test suite.
• tests/RobotFramework/tests/MQTT_health_check/mqtt_connection_status_with_incorrect_payload.robot https://github.com/thin-edge/thin-edge.io/pull/2257
• QA has tested the bug and could not reproduce it anymore.