## Summary of the Pull Request
#10297 found a bug in `ActionMap` where the `ToggleCommandPalette` key chord could not be found using `GetKeyBindingForAction`.
This was caused by the following:
- `AddAction`: when adding the action, the `ActionAndArgs` is basically added as `{ToggleCommandPalette, ToggleCommandLineArgs{}}` (Note the default ctor used for the action args)
- `GetKeyBindingForAction`: we're searching for an `ActionAndArgs` structured as `{ToggleCommandPalette, nullptr}`
- Since these are _technically_ two different actions, we are unable to find it.
This issue was fixed by making the `Hash(ActionAndArgs)` function smarter! If the `ActionAndArgs` has no args, but the `ShortcutAction` _supports_ args, generate the args using the default ctor.
By making `Hash()` smarter, everybody benefits from this logic! We can basically now enforce that `ActionAndArgs{ <X>, nullptr } == ActionAndArgs{ <X>, <default_ctor> }`.
## Validation Steps Performed
- Added a test.
- Tested this on #10297's branch and this does fix the bug
b3b648496e