我有一个表单，用户可以在其中填写他们的锻炼。我想调用addSet()并将一个FormGroup推送到sets FormArray

ngOnInit() {
       this.workoutForm = new FormArray([
          new FormGroup({
             name: new FormControl(),
             sets: new FormArray([
                new FormGroup({
                   reps: new FormControl(),
                   weight: new FormControl(),
                }),
             ]),
          })
       ]);
    }
    
     public addSet() {
       this.workoutForm.controls[0].controls.sets.push(
          new FormGroup({
             reps: new FormControl(),
             weight: new FormControl(),
          }),
       )
    }