QueryRewrite: implement complex cases of entity equality and enable relevant tests

[maumar]

example query:

from p in ps
where p.OrderDetails.Contains(
	ods.OrderByDescending(o => o.OrderID).ThenBy(o => o.ProductID)
		.FirstOrDefault(orderDetail => orderDetail.Quantity == 1))
select p

this can be translated to:

from p in ps
where p.OrderDetails.Select(x => x.Id).Contains(
	ods.OrderByDescending(o => o.OrderID).ThenBy(o => o.ProductID)
		.FirstOrDefault(orderDetail => orderDetail.Quantity == 1).Id)
select p

but in case of composite keys we need to be more creative, e.g.

from p in ps
where p.orderDetails.Join(
		ods.OrderByDescending(o => o.OrderID).ThenBy(o => o.ProductID)
			.Where(orderDetail => orderDetail.Quantity == 1).Take(1),
			p => { p.Key1, p.Key2 }, od => { od.Key1, od.Key2 }).Any()

[smitpatel]

Related #20164