in Sources/UberAuth/Authorize/PKCE.swift [63:72]
func convertToStringByReplacingCharacters(dict: [Character: Character]) -> String {
let string = self.base64EncodedString()
let stringArray: [Character] = string.map {
guard let val = dict[$0] else {
return $0
}
return val
}
return String(stringArray).trimmingCharacters(in: .whitespaces)
}