Update commands for recent versions of WordPress.

[peterwilsoncc]

Description of the Change

Update various commands and tests to account for upstream changes in recent versions of WP.

Fixes include:

• insert block selector updates
• closing welcome guide waits longer for it to appear
• delete all terms accounts for no terms being present
• updated selectors and order of operations for opening the sidebars

Closes #149

How to test the Change

1. Ensure E2E tests are passing for all versions of WP.

Changelog Entry

Changed - insertBlock updated to support WordPress 6.9.
Fixed - closeWelcomeGuide updated to allow for delayed render of guide.
Changed - deleteAllTerms updated to account for empty term lists and changes in WP 7.1.
Changed - openDocumentSettingsSidebar updated to account for changes in WP 7.1.

Credits

Props @dkotter, @peterwilsoncc.

Checklist:

• I agree to follow this project's Code of Conduct.
• I have updated the documentation accordingly.
• I have added Critical Flows, Test Cases, and/or End-to-End Tests to cover my change.
• All new and existing tests pass.

[peterwilsoncc]

@dkotter I can't approve officially as I opened the PR but I am happy with your changes. Thanks for the assist.