Sticky keys when using button combinations

### Is there an existing issue for this?

- [X] I searched the existing issues and did not find anything similar.

### Current Behavior

Whenever I map a button to two separate keys simultaneously (by joining them in the advanced menu), if you press on that button rapidly, the first key of that joined action doesn't release.

It get so bad that, when you press the button and look at the button highlight indicator, you can see the assigned keys change.

### Expected Behavior

I'd like to point out that in older versions of AntiMicro, this was never really an issue. It cropped up right after you guys added "X" to the name.

So, the expected behavior would be for the key to release immediately after the button is released.

### Steps To Reproduce

The controller in question is a Razer Raion Fightpad for the PS4. The button I'm assigning is R2.

Before

After:

Sometimes, when I press the R2 shoulder button, the application outright crashes. You may see that I have another button assigned to the same key (The R trigger). I don't know if that has something to do with it or not.

### Environment

```markdown
Program Version 3.1.4
compiled from packaging: 3.1.4-1 (Ubuntu hirsute/amd64)
Built Against SDL 2.0.14
Running With SDL 2.0.20
Using Qt 5.15.3
Using Event Handler: XTest
```

### Anything else?

_No response_