Hotkeys are not deleted when pressing [Delete] in input options

[valkyrienyanko]

⚠️ You should be familiar with how the hotkey system works before tackling this issue. In-game press esc, go to options, hotkeys and add / remove keybinds.

Steps to Reproduce

1. Double click on res://Framework/Scenes/Options/Options.tscn and run this scene with F6
2. Go to Options > Input, click on the +, add a new keybind
3. Select the hotkey you just created and delete it with the [Delete] key
4. Press Esc to go back to the main menu
5. Go back to Options > Input and notice the key you deleted came back

Observations

• Pressing Reset to Defaults will delete all newly added keys with 100% success. So why isn't it working when deleting a specific key?

Suggestions

• Redo all of the hotkey code from scratch.

Reminders

• Due to the massive amount of information required for each input action, we are forced to make use of Godot's resource system and as such this is something that cannot be moved to a separate assembly.