There's a new way to specify RxJS error and complete callbacks

[Jane Sandberg]

We're accustomed to calling subscribe() and tap() with up to three arguments: the first is a next callback, the second is an error callback, and the third is a complete callback. However, this is now deprecated (https://rxjs.dev/deprecations/subscribe-arguments) in favor of a syntax that is more obvious to read. No longer do you have to count arguments to figure out which callback is which, it is nicely labeled as an object in the first argument, e.g.:

$myObservable.subscribe({next: myNextCallback, error: myErrorCallback, complete: myCompleteCallback})

We should update all our subscribes and taps to match the new syntax before the old syntax is removed.