docs(compat): fix typo in readme (#3638)
docs(compat): fix typo in readme (#3638)

fix typo in readme referring to previous (pervious) RxJS versions
ReactiveX/RxJS,benlesh/RxJS,trxcllnt/RxJS,trxcllnt/RxJS,martinsik/rxjs,martinsik/rxjs,ReactiveX/rxjs,Brocco/RxJS,benlesh/RxJS,ReactiveX/rxjs,ReactiveX/RxJS,benlesh/RxJS,ReactiveX/RxJS,kwonoj/RxJS,ReactiveX/rxjs,Brocco/RxJS,trxcllnt/RxJS,kwonoj/RxJS,kwonoj/RxJS,ReactiveX/RxJS,martinsik/rxjs,martinsik/rxjs,trxcllnt/RxJS,Brocco/RxJS,ReactiveX/rxjs,kwonoj/RxJS,benlesh/RxJS,Brocco/RxJS