[Picker Input]: Shift+Tab doesn't move focus to the previous field

[NatalliaAlieva]

Description

When navigating through the form (or smth else) using the keyboard, the focus gets stuck on the Single Picker Input field. The Shift+Tab shortcut, which should move the focus to the previous field, does not work.

Steps to Reproduce

1. Open the Demo -> Form.
2. Use the Tab key to navigate to the 'Country' field (Single Picker Input).
3. Press Shift+Tab to move back to the previous field.

Actual Result:

The focus remains on the Single Picker Input field, preventing backward navigation.

Screen.Recording.2025-03-06.at.16.07.49.mov

Expected Result:

Pressing Shift+Tab should move the focus to the previous field as expected.

Environment

• UUI version: 5.13.2
• Browser name: any
• Operating System: any