Make Jetpack Forms dashboard use the "Feedback" menu item in WP Admin

[ice9js]

Proposed changes:

This patch updates the WP Admin sidebar configuration so the JP Forms dashboard replaces the existing "Feedback" entry.
At the same time, the old feedback admin page can still be accessed under /wp-admin/edit.php?post_type=feedback, which is intentional until we've reached full feature parity and the old interface can be deprecated.

In the short-term, we'll likely add a link or possibly a user meta setting allowing users to choose what interface they prefer to interact with. It'll be a separate PR as we're still figuring that out.

Other information:

• Have you written new tests for your changes, if applicable?
• Have you checked the E2E test CI results, and verified that your changes do not break them?
• Have you tested your changes on WordPress.com, if applicable (if so, you'll see a generated comment below with a script to run)?

Jetpack product discussion

pcsBup-Pl-p2

Does this pull request change what data or activity we track or use?

No.

Testing instructions:

Enable the new dashboard with these filters:

add_filter( 'jetpack_contact_form_use_package', '__return_true' );
add_filter( 'jetpack_forms_dashboard_enable', '__return_true' );

• Verify that when the dashboard is enabled, the "Feedback" top-level sidebar item links to the new dashboard and not the default WP Admin interface for feedback.
• The default feedback admin should still be available when accessing the URL manually: /wp-admin/edit.php?post_type=feedback.

[github-actions]

Are you an Automattician? You can now test your Pull Request on WordPress.com. On your sandbox, run

bin/jetpack-downloader test jetpack add/jetpack-forms-dashboard-toggle

to get started. More details: p9dueE-5Nn-p2

[github-actions]

Thank you for your PR!

When contributing to Jetpack, we have a few suggestions that can help us test and review your patch:

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Jetpack plugin:

• Next scheduled release: March 7, 2023.
• Scheduled code freeze: February 28, 2023.