Page Optimize Bail: Avoid asset concatenation when opening the site editor

[jeyip]

Description

Potentially fixes Automattic/wp-calypso#54459

This is a hotfix to prevent loading an editor reset stylesheet in the Gutenberg Site Editor. We are attempting to merge changes into core Gutenberg that will address the underlying bug, at which point the changes made in this PR can be removed.

This PR causes the page-optimize plugin to bail if loading assets for the Gutenberg Site Editor.

An alternative hotfix can be found in 738-gh-Automattic/wpcomsh

Steps to Reproduce

• With a block based theme activated, load the site editor with the page optimize plugin enabled
• Verify that wp-reset-editor-styles is not loaded, by searching the page markup for the stylesheet id (wp-reset-editor-styles-css) and/or checking to make sure the styles are not applied to .editor-styles-wrapper within the iframe
• Also load the post editor to make sure the styles reset continues to load there

[jeyip]

Closing this PR for now since we merged an alternative Hotfix solution in the wpcomsh repo 738-gh-Automattic/wpcomsh