iOS 14 support

[VladimirLyseev]

It doesn't work on iOS 14. Do you know how to fix it?

[VladimirJph]

Solved. iOS 14 expects NSCTVariationAxisIdentifier as NSNumber instead of NSCTVariationAxisName in attributionDictionary.

var attributesDict = [NSNumber: Any]()
attributes.forEach {
    attributesDict[$0.identifier] = $0.currentValue
}

Change identifier type to NSNumber

[chrszlz]

Happy to merge a PR if you have one @VladimirJph @VladimirJph