Add mqtt sensor configurable state encoding for sensor and binary_sensor platform (#60447)

* Add mqtt sensor state encoding

* Make encoding attribute not specific to states

* Move encoding attribute to schema base

homeassistant/components/mqtt/trigger.py

@@ -10,13 +10,10 @@ from homeassistant.core import HassJob, callback
 from homeassistant.helpers import config_validation as cv, template
 
 from .. import mqtt
-from .const import CONF_QOS, CONF_TOPIC
+from .const import CONF_ENCODING, CONF_QOS, CONF_TOPIC, DEFAULT_ENCODING, DEFAULT_QOS
 
 # mypy: allow-untyped-defs
 
-CONF_ENCODING = "encoding"
-DEFAULT_ENCODING = "utf-8"
-DEFAULT_QOS = 0
 
 TRIGGER_SCHEMA = cv.TRIGGER_BASE_SCHEMA.extend(
     {