Get the list of items for the specific recommendation slot.
You can pass an array of rules to the widget to filer widget results.
An example of rules object for different types of data:
[{
type: 'text',
name: 'brand',
values: [{value: ['Some-Test-Brand']}, {value: ['Some-Other-Brand']}]
}, {
type: 'range',
name: 'price',
values: [{from: 10}, {to: 20}, {from: 10, to: 20}]
}, {
type: 'category',
name: 'category',
values: [{value: ['Top-Level']}, {value: ['Top-Level', 'Second-level']}]
}]