Amplify effect is not removed correctly with burst fire

[M3r1st]

Due to how X2AbilityMultiTarget_BurstFire is handled, abilities like Fan Fire can cause the counter to skip the value required for it to be removed.

if (AmplifyState.ShotsRemaining == 1)
{
	AmplifyState.RemoveEffect(NewGameState, NewGameState);
}
else
{
	AmplifyState = XComGameState_Effect_Amplify(NewGameState.ModifyStateObject(AmplifyState.Class, AmplifyState.ObjectID));
	AmplifyState.ShotsRemaining -= 1;
}