Add device class support to text sensor (#6202)

Co-authored-by: Jesse Hills <3060199+jesserockz@users.noreply.github.com>

esphome/components/api/api_connection.cpp

@@ -543,6 +543,7 @@ bool APIConnection::send_text_sensor_info(text_sensor::TextSensor *text_sensor)
   msg.icon = text_sensor->get_icon();
   msg.disabled_by_default = text_sensor->is_disabled_by_default();
   msg.entity_category = static_cast<enums::EntityCategory>(text_sensor->get_entity_category());
+  msg.device_class = text_sensor->get_device_class();
   return this->send_list_entities_text_sensor_response(msg);
 }
 #endif