Making a group attack doubles up on the modifier and proficiency bonuses

[kaelad02]

This is done without Midi QOL, just the core roller.

I created a 1/4 CR minion from the Flee Mortals book. It had a +1 ability modifier for the attack and a +2 from proficiency bonus. I made an attack with a group weapon. I got the popup asking me how many minions were involved and I just put 1. Then the normal attack dialog showed up with the following formula: 1d20 + 1 + 2 + 1 + 2 + 1 (doing it from memory, I think that was the order). It seems like it was including the ability modifier and proficiency bonus twice.

I took a look at the code and I think I see the bug. In scripts/plugins/vanilla.js starting at line 35. That's the code that triggers after entering the number of minions making the attack. The normal hook cancels the attack roll by returning false (line 54) and then restarts it by calling rollAttack on line 50. It's passing the rollConfig to that function, which already has parts filled in and I believe that's why the ability modifier and proficiency bonus are doubled up since they'll be added to what rollAttack already generates.