message: Typescript make ActionSheet parameters optional
  Change cancelButtonIndex and destructiveButtonIndex to be optional
diff: @@ -924,8 +924,8 @@ declare module "native-base" {
  static show: (
  configuration: {
  options: string[];
  - cancelButtonIndex: number;
  - destructiveButtonIndex: number;
  + cancelButtonIndex?: number;
  + destructiveButtonIndex?: number;
  title: string;
  },
  onSelect: (index: number) => void
  