Clear combo timer only when affected keys are released

[ssbb]

Now, the key release listener checks if the released key is part of any combo candidate or active combo, instead of stopping the combo timer on any key release.

I also had to modify the tap-dance/3b-tap-int-seq test because it relied on the old combo release behavior, but I would like to double-check if this is the behavior we want to maintain.

Fixes #2378