increase weight reducer of "previous_trials" logic for random attacks

[TheAfroOfDoom]

Summary

Currently, we reduced the weight of the previously-ran attack through the random attack from 2 -> 1.

#29 has more details, but as an example:

before

if the base weights for attacks were:

attack	x-bullets-lower	x-bullets-upper	finger-guns
base weight	2	2	2
probability of being chosen	33%	33%	33%

and we run the random attack -> it runs finger-guns, the weights/probabilities become:

attack	x-bullets-lower	x-bullets-upper	finger-guns
weight	2	2	1
probability of being chosen	40%	40%	20%

after

in this PR, we increase the base weights from 2 -> 3 and increase the weight reducer from 1 -> 2. this changes the previously-ran attack table to:

attack	x-bullets-lower	x-bullets-upper	finger-guns
weight	3	3	1
probability of being chosen	43%	43%	14%

TL;DR

we are making it so if an attack runs from the randomizer, we have an even smaller chance of running it again compared to previously

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Test plan

tested in-game with the same test strategies found in #29

Reproducing in-game

from #29

This specifically is intended to make the attacks ran by the boss fight not repeat back-to-back as often. So run the boss fight with the following commands to see how it feels:

function _:reset
function _:boss_fight

Preview

N/A

its just adjusting random weights

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Supplemental changes

N/A