title: Angular HttpInterceptor - argument type not assignable
body: <p>I would like to create custom HttpInterceptor to validate if HttpResponse has status 403 - if so, display a monit to user. Basing on some tutorials I've written the following piece of code:</p>
  
  <pre><code>@Injectable()
  export class 403HttpInterceptor implements HttpInterceptor{
  
   constructor(){}
  
   intercept(request: HttpRequest&lt;any&gt;, next: HttpHandler): Observable&lt;HttpEvent&lt;any&gt;&gt;{
  
  return next.handle(request).pipe(
    catchError((err:HttpErrorResponse)=&gt;{
     if(err.status === 403){
      //display monit
     }
     return throwError(err);
  })
  );
  }
  }
  </code></pre>
  
  <p>However still getting </p>
  
  <blockquote>
    <p>Argument type (err:HttpErrorResponse) => Observable is not
    assignable to parameter type (err:any, caught:Observable)=>never</p>
  </blockquote>
  
  <p>Using Angular 7.2.10 and rxjs 6.4.0</p>