[Core] Investigate if spell school resistances still work @ lvl 90

[1337LutZ]

Test if spell (level based) resists are still relevant @ lvl 90 as old Blue posts mention it being removed. However testing proved that @ lvl 85 trinkets such as the Baradin Hold Resistance trinket still works. Perhaps this is related to max level only.

Reference PR: #74

Lvl 90 (vs 87 mob) not resisting any damage with Mirror active:
https://classic.warcraftlogs.com/reports/dZ8gjA9mhNMwtQD2?boss=-3&difficulty=0&type=damage-taken&ability=121601&view=events

Lvl 85

Blizzard sources:

1. https://www.bluetracker.gg/wow/topic/us-en/4138435594-elemental-damage-should-matter/
2. https://www.bluetracker.gg/wow/topic/eu-en/3780044-coffee-with-the-devs-mists-of-pandaria-stat-changes/

[InDebt]

https://wowpedia.fandom.com/wiki/Resistance

To add on to this. While not explicitly stated in this arcticle, it can be easily observed that even during cataclysm there was no longer level based reistances. That are those resistances gained by an enemy just by being a higher level than the attacker. I think that is even commented in the code. We still left the basic resistance formula in as players could gain resistances through trinkets and gear to resist elemental attacks.

Those mechanics now seem to also be heavily dinished as only legacy items may keep pure resistances on them. So I think resistences are indeed nothing we will have to support for any level 90 encounter

[1337LutZ]

Closing this issue as we have removed resistances.