fix: polyfill SVGElement.prototype.contains for IE

src/polyfills.js

@@ -6,3 +6,5 @@ import "element-remove"
 import "classlist-polyfill"
 import "@webcomponents/template"
 import "custom-event-polyfill"
+
+SVGElement.prototype.contains = SVGElement.prototype.contains || HTMLElement.prototype.contains