Refactor: convert initializeApp to func component and use JSX transform in the codebase (#4056)

src/tests/binding.test.tsx

@@ -1,4 +1,3 @@
-import React from "react";
 import { fireEvent, render } from "./test-utils";
 import ExcalidrawApp from "../excalidraw-app";
 import { UI, Pointer, Keyboard } from "./helpers/ui";