Add typemustmatch property on <object>

As reported in TypeScript issue #20756:
microsoft/TypeScript#20756

Spec here:
https://html.spec.whatwg.org/multipage/iframe-embed-object.html#attr-object-typemustmatch

Author: Vinnl

baselines/dom.generated.d.ts

@@ -6062,6 +6062,7 @@ interface HTMLObjectElement extends HTMLElement, GetSVGDocument {
      * Returns whether an element will successfully validate based on forms validation rules and constraints.
      */
     readonly willValidate: boolean;
+    typemustmatch: boolean;
     /**
      * Returns whether a form will validate when it is submitted, without having to submit it.
      */

inputfiles/addedTypes.json

@@ -2476,6 +2476,12 @@
         "name": "control",
         "type": "HTMLInputElement | null"
     },
+    {
+        "kind": "property",
+        "interface": "HTMLObjectElement",
+        "name": "typemustmatch",
+        "type": "boolean"
+    },
     {
         "kind": "property",
         "interface": "File",