Generate child igx-hierarchical-grids dynamically

[kdinev]

Is your feature request related to a problem? Please describe.

Currently, child igx-hierarchical-grid components are static children of the igx-child-grid-row and the igx-child-grid-row is part of the igx-hierarchical-grid template. While using NgModule and at runtime, this isn't a problem because the template holding the igx-child-grid-row is created dynamically. However, in a standalone component scenario, this is a problem, because the IgxChildGridRowComponent depends on and imports IgxHierarchicalGridComponent and vice versa. This creates a cyclical import when the hierarhical grid component used in an app as a standalone component.

Describe the solution you'd like

The igx-hierarhical-grid doesn't have to be a static child of the igx-child-grid-row and can instead be created dynamically using the new createComponent api.

Describe alternatives you've considered

There hasn't been any alternative that I've discovered so far.

Additional context

The issue can be seen in #12699. Just run any of the hierarchical grid tests.

UPDATE: ComponentFactory and ComponentFactoryResolver are being removed in Angular 16. We have to get rid of all of the usage of these APIs.