Core: MQTT Alarm doesn't activate via scenes using activation code

[KC-inDomus]

Home Assistant release with the issue:
0.102.1

Last working Home Assistant release (if known):
0.100.3

Operating environment (Hass.io/Docker/Windows/etc.):
Venv on Raspbian

Integration:
N/A

Description of problem:
MQTT code-protected alarm doens't activate only when using scenes:

[homeassistant.components.mqtt.alarm_control_panel] Wrong code entered for arming away

Code isn't wrong - it was working good on 0.100.x - and it works from frontend.
Config:

alarm_control_panel:
- platform: mqtt
  name: Alarm
  code: 1234
  state_topic: "stat/Alarm"
  command_topic: "cmnd/Alarm"
  payload_arm_home: "armed_home"
  payload_arm_away: "armed_away"
  payload_disarm: "disarmed"
  qos: 2

scenes:
- name: Away
  entities:
    alarm_control_panel.alarm:
      state: armed_away
      code: 1234

[probot-home-assistant[bot]]

Hey there @home-assistant/core, mind taking a look at this issue as its been labeled with a integration (mqtt) you are listed as a codeowner for? Thanks!

[probot-home-assistant[bot]]

Hey there @colinodell, mind taking a look at this issue as its been labeled with a integration (alarm_control_panel) you are listed as a codeowner for? Thanks!

[KC-inDomus]

hi @colinodell, did u have a chance to take a look?

[probot-home-assistant[bot]]

Hey there @home-assistant/core, mind taking a look at this issue as its been labeled with a integration (scene) you are listed as a codeowner for? Thanks!

[balloob]

This is no longer supported. Scenes only replicate an existing state, and alarm code is not part of that state. You will need to use a service call to activate an alarm.