react-dom: Revert test change (#19280)

types/react-dom/react-dom-tests.ts

@@ -55,7 +55,7 @@ describe('React dom test utils', () => {
             React.createElement('input', { type: 'text' }),
             element
         ) as Element;
-        const node = ReactDOM.findDOMNode(dom);
+        const node = ReactDOM.findDOMNode(dom) as HTMLInputElement;
 
         node.value = 'giraffe';
         ReactTestUtils.Simulate.change(node);

types/react-dom/tslint.json

@@ -1,6 +1,7 @@
 {
     "extends": "dtslint/dt.json",
     "rules": {
-        "dt-header": false
+        "dt-header": false,
+        "no-unnecessary-type-assertion": false
     }
 }