Angular 13 - How to resolve '(): Promise<Object | undefined>' is deprecated.ts(6385)

Question

In my Angular-13 project, I am trying to get the data from API endpoint for chartjs. I have this in the service:

  getCurrentEmployeeChart() {
    return this.http.get(this.baseUrl + 'current-employee')
        .toPromise()
        .then((data) => {
          return data;
        });
  }

I got this error:

'(): Promise<Object | undefined>' is deprecated.ts(6385) Observable.d.ts(125, 9): The declaration was marked as deprecated here.

Then:

toPromise()

is crossed.

How do I resolve this?

Thanks