Fix increased Enemy damage taken mods doubling their affect in Ailment calcs

[Andrew-Klotz]

Fixes bug with no outstanding issue.

Description of the problem being solved:

Increases/more damage taken on enemies is double counted for physical/chaos ailments (bleed and poison). E.g., Nearby enemies take 10% increased chaos damage results in a 20% increase in the calculations.

Steps taken to verify a working solution:

Confirmed physical/chaos work properly for bleed/poison respectively, while elemental still works for ignite.

Link to a build that showcases this PR:

https://pobb.in/UCOPSE85Cyoz

Before screenshot:

After screenshot:

[Andrew-Klotz]

Looks good to me. I kept the ailmentTypeMod path as future proofing for other generic damage modifiers that could be added (e.g. non-chaos), but currently the game only has elemental so your cleaner fix works.

As for testing, didn't add any as I was unsure on testing philosophy (test count looks fairly light given the project size, and contributing.md just mentions adding testing for new features) and didn't know how much of a performance bottleneck there might be on testing. Depending on philosophy, it might be worth considering adding testing for increased phys for bleed and increased fire/elemental for ignite. Current dev has the same double-count for phys bleed as for chaos poison.