Update IframeHTMLAttributes

- resolves wonderful-panda#102
- adds `allow` and `referrerpolicy` to interface in "types/dom.d.ts"

Author: moonquddus

types/dom.d.ts

@@ -129,13 +129,15 @@ export interface HtmlHTMLAttributes extends HTMLAttributes {
 }
 
 export interface IframeHTMLAttributes extends HTMLAttributes {
+  allow?: string;
   allowfullscreen?: boolean;
   allowtransparency?: boolean;
   frameborder?: number | string;
   height?: number | string;
   marginheight?: number;
   marginwidth?: number;
   name?: string;
+  referrerpolicy?: string;
   sandbox?: string;
   scrolling?: string;
   seamless?: boolean;