Handle null filters value within the pivot configuration in the data selector component

[3phase]

Related to #10736

Description

The IPivotConfiguration does not require the filters-property and defaults to null if it's not present, so the case when there's no filters in the configuration should be handled in order to avoid the error below.

• igniteui-angular version:
• browser:

Steps to reproduce

1. Set the filters in the pivot configuration within the pivot dev-sample to null
2. Open the sample and observe the error

Result

Expected result

What is the expected result after following the steps to reproduce?

Attachments

Attach a sample if available, and screenshots, if applicable.