Update 'Binding Items to Components' chapter with last version of ComboBox with data view

[mshabarov]

Update this chapter https://vaadin.com/docs/v17/flow/binding-data/tutorial-flow-data-provider.html according to the last changes in ComboBox regards support of data view API.

The following features should be described for ComboBox:

1. Filtering with Lazy Data Binding.
2. Usage of the data fetch callbacks / data providers with a custom filter type (not a String). How to set a filter converter
3. Combo Box items count change notifications. Show that the client-side filter change does not fire the event.
4. Accessing Currently Shown Items. Specify that the client-side filter will not affect the items returned by DataView::getItems().

[mshabarov]

Here is the notes of DX test https://docs.google.com/document/d/16gGlfnXxPdrzKbFqNuv0MG9LFMrUxN4ZAbOx3nJe6J8/edit?usp=sharing

And the other DX docs https://drive.google.com/drive/u/1/folders/1VMYf8lx10jbB-uFVfMlLKdizcziPAtla