Custom sorting indicator templates don't work

[fvitolo]

Description

Trying to set up a custom sorting indicator template as described in the guide in section https://www.infragistics.com/products/ignite-ui-react/react/components/grids/grid/sorting#sorting-indicators-templates, I get the following type mismatch error: ....

TS2322: Type
(ctx: IgrGridHeaderTemplateContext) => Element
is not assignable to type
FunctionComponent<{ dataContext: IgrGridHeaderTemplateContext; }> | Component<{ dataContext: IgrGridHeaderTemplateContext; }, {}, any> | undefined
Type
(ctx: IgrGridHeaderTemplateContext) => Element
is not assignable to type
FunctionComponent<{ dataContext: IgrGridHeaderTemplateContext; }>
Types of parameters  ctx  and  props  are incompatible.
Type
PropsWithChildren<{ dataContext: IgrGridHeaderTemplateContext; }>
is missing the following properties from type  IgrGridHeaderTemplateContext :
createImplementation, _implementation, mounted, nativeElement , and  7  more.
igr-grid-base-directive.d.ts(1401, 5): The expected type comes from property  sortHeaderIconTemplate  which is declared here on type
IntrinsicAttributes & IntrinsicClassAttributes<IgrGrid> & Readonly<IIgrGridProps> & Readonly<...>

When I try to use a React.FunctionComponent like this

    const sortHeaderIconTemplate: React.FunctionComponent<{
      dataContext: IgrGridHeaderTemplateContext;
    }> = ({ dataContext }) => {
      console.log(dataContext);
      return 
         <>
            <IgrIcon name='unfold_more'></IgrIcon>
        </>;
    };

instead, I receive the following error in the console:

runtime.js:101 ERROR 
Error: Element type is invalid: expected a string (for built-in components) or a class/function (for composite components) but got: null.

Check the render method of `IgrGrid2`.

What is the correct way to use this property?