Hold/Toggle control settings not working

[shoftmadder]

Bug reported on Reddit:
https://www.reddit.com/r/assettocorsa/comments/10ohedi/content_manager_turn_signals_holdtoggle/

Setting the HOLD_MODE=1 in the relevant section in config.ini works in-game, but the setting doesn't appear to be read or written in Content Manager

Have had a quick look through the relevant code, but couldn't see anything obviously wrong:
https://github.com/gro-ove/actools/blob/master/AcManager.Tools/Helpers/AcSettings/ControlsSettings.cs#L1573
https://github.com/gro-ove/actools/blob/master/AcManager.Tools/Helpers/AcSettings/ControlsSettings.cs#L1685
https://github.com/gro-ove/actools/blob/master/AcManager.Tools/Helpers/AcSettingsControls/CustomButtonEntryCombined.cs
https://github.com/gro-ove/actools/blob/master/AcManager/Pages/AcSettings/AcSettingsControls_Wheel_Patch.xaml#L90