Autodiscovery for Home Assistant only uses default topic for config messages

[Bodrick01]

**Summary
I don't use the default autodiscovery MQTT topic of "homeassistant" within my Home Assistant (HA) environment.

If I configure an OMG device (eg lilygo-ble) and set the base topic to be the same as my defined autodicovery topic in HA then the detected sensor values are indeed published with this base topic.

However, it appears that the "config" messages are only published under the default base topic of "homeassistant" and not under my required topic. Hence they are never then autodiscovered by HA.

Please can this be confirmed/resolved.

Describe the bug
Config messages for Home Assistant are only published under the default topic of "homeassistant" and not under any custom topic specified on the OMG gateway.

To Reproduce
Steps to reproduce the behaviour:

1. install pre-compiled binary - I used lilygo-ble
2. choose a base topic that isn't "homeassistant"
3. watch the data received on the OMG gateway being published using MQTTExplorer
4. note that the "config" messages continue to only be published under the "homeassistant" topic and not the specified base topic

Expected behaviour
I would expect config messages to be published under the specified topic.

Environment (please complete the following information):

• OpenMQTTGateway version v1.7.0 used, pre-compiled binary loaded directly from web site