Merge branch 'polyfill-url' into 'master'

Import url-polyfill in the root

See merge request !11

dist/index.d.ts

+import "url-polyfill";
 export { default as HTMLNormalizer } from "./HTMLNormalizer";
 export { default as PlainNormalizer } from "./PlainNormalizer";
 export { EMAIL_VENDORS } from "./constants";

dist/index.js

 "use strict";
 Object.defineProperty(exports, "__esModule", { value: true });
 exports.EMAIL_VENDORS = exports.PlainNormalizer = exports.HTMLNormalizer = void 0;
+require("url-polyfill");
 var HTMLNormalizer_1 = require("./HTMLNormalizer");
 Object.defineProperty(exports, "HTMLNormalizer", { enumerable: true, get: function () { return HTMLNormalizer_1.default; } });
 var PlainNormalizer_1 = require("./PlainNormalizer");

src/index.ts

+import "url-polyfill";
+
 export { default as HTMLNormalizer } from "./HTMLNormalizer";
 export { default as PlainNormalizer } from "./PlainNormalizer";