react-aria: drop typing workaround

This was fixed upstream.

src/react-aria.d.ts

@@ -1,13 +0,0 @@
-// SPDX-License-Identifier: MIT
-// Copyright (c) 2022 The Pybricks Authors
-
-// exposes some monaco editor internal functions
-
-import {} from 'react-aria';
-
-declare module 'react-aria' {
-    export interface OverlayContainerProps {
-        // work around https://github.com/adobe/react-spectrum/issues/3375
-        className: string;
-    }
-}