Proposed change

If non deprecated MQTT config settings are in configuration.yaml A user will still get a deprecation warning for values that have a default value through config validation.

        vol.Optional(CONF_PORT, default=DEFAULT_PORT): cv.port,
        vol.Optional(CONF_WILL_MESSAGE, default=DEFAULT_WILL): MQTT_WILL_BIRTH_SCHEMA,
        vol.Optional(CONF_BIRTH_MESSAGE, default=DEFAULT_BIRTH): MQTT_WILL_BIRTH_SCHEMA,
        vol.Optional(CONF_DISCOVERY, default=DEFAULT_DISCOVERY): cv.boolean,

The defaults have be removed from the config validation to avoid the false positive deprecation warnings.
When the configuration is merged this based on the default values.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
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