Add ContainedStereotypes property to ContentPickerFieldSettings to allow a user to include content-types by steryotype

[MikeAlhayek]

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

When attaching ContentPickerField to a content part, the user must explicitly set DisplayedContentTypes with an array of content-types to be include in the ContentPickerField. This is good for most case, however, it would be great to allow for setting the contained content-types using Stereotype. Stereotype would be in addition to not in place of DisplayedContentTypes.

For example, I want to group all todo items (appointment, meeting) by a stereotype type called ToDoTask. All of these content types share similar functionally which is a todo task. Now I want to use ContentPickerField in a different content type to allow the user to select a todo-task of any kind. In this case, I have to explicitly specific each content types that in the DisplayedContentTypes. But if a new content-type was added later "from other feature/module", the user would have manually to edit the ContentPickerField settings every time/every where todo task are used to add the new content-type which it isn't efficient.

Describe the solution you'd like

Add a way to specific a stereotypes in the ContentPickerFieldSettings in addition to DisplayedContentTypes so the user is able to explicitly able to set displayed-content-types or explicitly set the stereotype.

We can achieve this by changing the ContentPickerFieldSettings to something like this

public class BagPartSettings
{
    public string Hint { get; set; }
    public bool Required { get; set; }
    public bool Multiple { get; set; }
    public bool DisplayAllContentTypes { get; set; } = Array.Empty<string>();
    public string[] DisplayedContentTypes { get; set; } = Array.Empty<string>();
    public string[] DisplayedStereotypes { get; set; } = Array.Empty<string>();
}

[MikeAlhayek]

This request is related to #11977