Fix calculation error with theoretical maximum poison stacks

[majochem]

Description of the problem being solved:

My previous calculation of the theoretical maximum poison stacks used a value for singleHitPoisonStacks that also took into account hit chance and poison chance. However, that incorrectly assumed that a fraction of the additionalPoisonStacks could be applied, leading to higher theoretical maximums.

As a result, lowering your hit chance or poison chance could lead to higher actual poison DPS which is obviously not true. (except the edge cases when lowering hit/poison chance puts you below the threshold for "non-Poisoned Enemy")

Steps taken to verify a working solution:

• Tested with lower poison chance and now value does not exceed actual theoretical maximum

Link to a build that showcases this PR:

Test Build
(see config mods for easy reproduction of wrong value in current version)

Before screenshot:

95% poison chance leads to 13.44 poison stacks

After screenshot:

Poison stacks correctly limited to 12