chore(observeOn): fix skipped test
chore(observeOn): fix skipped test

Closes #2457 #2459

ReactiveX/RxJS,ReactiveX/RxJS,trxcllnt/RxJS,martinsik/rxjs,martinsik/rxjs,kwonoj/RxJS,benlesh/RxJS,Brocco/RxJS,martinsik/rxjs,benlesh/RxJS,ReactiveX/rxjs,ReactiveX/RxJS,kwonoj/RxJS,Brocco/RxJS,trxcllnt/RxJS,Brocco/RxJS,ReactiveX/rxjs,martinsik/rxjs,ReactiveX/rxjs,ReactiveX/RxJS,benlesh/RxJS,benlesh/RxJS,kwonoj/RxJS,kwonoj/RxJS,trxcllnt/RxJS,trxcllnt/RxJS,Brocco/RxJS,ReactiveX/rxjs