message: Add new CI builder configs to mb_config.pyl.
  TBR=titovartem@webrtc.org
  Cr-Commit-Position: refs/heads/master@{#32555}
diff: 'iOS32 Release': 'ios_release_bot_arm',
  'iOS64 Debug': 'ios_debug_bot_arm64',
  'iOS64 Release': 'ios_release_bot_arm64',
  - 'iOS64 Sim Debug (iOS 10.0)': 'ios_debug_bot_x64',
  - 'iOS64 Sim Debug (iOS 11)': 'ios_debug_bot_x64',
  'iOS64 Sim Debug (iOS 12)': 'ios_debug_bot_x64',
  + 'iOS64 Sim Debug (iOS 13)': 'ios_debug_bot_x64',
  + 'iOS64 Sim Debug (iOS 14.0)': 'ios_debug_bot_x64',
  # Mac
  'Mac64 Debug': 'debug_bot_x64',
  