Fix for Chieftain resist nodes applying effects twice due to Foulborn Choir of the Storm

[EminGul]

Fixes #9481 .

Description of the problem being solved:

Foulborn Choir of the Storm's increased mana by overcapped lightning resist mod causes resistance conversion mods, such as Taslio, Cleansing Water, to apply twice in calculations.

This is due to how Foulborn Choir of the Storm is handled in the calculations. Since it calls the resistance, mana and reservation calculations again, it adds resistance conversion mods twice as well.

Fix just adds a flag so resistance conversion mods aren't processed twice on accident.

Steps taken to verify a working solution:

• Check resists are accurate: ~25,000 fire resistance with ~12,500 lightning and cold resistance
• Check Max res granted by Valako, Storm's Embrace is not double applying to cold/lightning resist
• Check Mana to Energy Shield no longer double applying and matches with user report
• Check Transfiguration of Mind applies half the increased damage (in config)
• Check if non-Foulborn Choir builds have resist/max res from Chieftain nodes works properly

Link to a build that showcases this PR:

https://pobb.in/5cSHvaw15MUI (Screenshots based off this PoB)

https://pobb.in/V41O4IvnojAr (extra case, ES aligns with user report but I'm uncertain mana is accurate as they're saying the in-game UI is bugged. The increased mana aligns with what they're reporting.)

Before screenshot:

After screenshot:

[LocalIdentity]

I changed it to use a fake actor and also added a test in case this breaks again in the future