Method purchase

src/plugins/iap/index.d.ts:20–20

(
    skuId: string,
    onSuccess: (responseCode: number) => void,
    onError: (err: string) => void,
  )

    onError: (err: string) => void,
  ): void;
  purchase(
    skuId: string,
    onSuccess: (responseCode: number) => void,
    onError: (err: string) => void,