Normally functions that return `ModuleWithProvider` objects should parameterize
the return type to include the type of `NgModule` that is being returned. For
example `forRoot(): ModuleWithProviders<RouterModule>`.
But in some cases, especially those generated by nccc, these functions to not
explicitly declare `ModuleWithProviders` as their return type. Instead they
return a "intersection" type, one of whose members is a type literal that
declares the `NgModule` type returned. For example:
`forRoot(): CustomType&{ngModule:RouterModule}`.
This commit changes the `NgModuleDecoratorHandler` so that it can extract
the `NgModule` type from either kind of declaration.
PR Close#27326