Support for WICG Observable

### What is the problem this feature will solve? This new proposal adds `.when` method to `EventTarget`, then we can control event handling using Observable API. Example from the spec: ```js // Filtering and mapping: element .when('click') .filter((e) => e.target.matches('.foo')) .map((e) => ({ x: e.clientX, y: e.clientY })) .subscribe({ next: handleClickAtPoint }); ``` Spec: https://github.com/WICG/Observable Standard Tracking: https://github.com/WICG/observable/issues/93 This is something that makes sense to implement on Node? ### What is the feature you are proposing to solve the problem? Basically implements the new `.when` method at: https://github.com/nodejs/node/blob/a0ac8bd4d85e5614f43e4fed3e0c73641cd45fa8/lib/internal/event_target.js#L551 ### What alternatives have you considered? The @benlesh (contributor of the spec) looks like he already tried to implement this new spec at https://github.com/nodejs/node/pull/51065