Refactor: automatically open sidebar block menu on build preview

[JoshuaHungDinh]

Resolves # GIVE-536

Description

When opening the build section of the visual form builder we want the left sidebar menu set to open automatically as a way to ensure users can easily find new blocks to add.

The state that manages which sidebar is open can be found as selectedSecondarySidebar in the BlockEditorInterfaceSkeletonContainer component. This state manages both the list view and the block menu.

This PR applies the name of the sidebar add as a default for the open state that manages the secondary sidebar which will ensure that the block menu is open when selecting the build preview section.

Additionally an unused import was removed.

Affects

• Visual Form Builder
• Sidebars

Visuals

Screen.Recording.2024-03-26.at.3.20.46.PM.mov

Testing Instructions

• Create a v3 form
• Select the build section to verify the left sidebar with the block menu opens automatically.
• Test out the other sidebars in both the build & design preview sections.

Pre-review Checklist

• Acceptance criteria satisfied and marked in related issue
• Relevant @unreleased tags included in DocBlocks
• Includes unit tests
• Reviewed by the designer (if follows a design)
• Self Review of code and UX completed

[jonwaldstein]

Magnificent! 🥇

[rickalday]

Passed manual QA tests.