VisualEditor: Always output has-global-padding classname when in post…

… only mode and the site supports root padding aware alignments (WordPress#66626)

Co-authored-by: andrewserong <andrewserong@git.wordpress.org>
Co-authored-by: ramonjd <ramonopoly@git.wordpress.org>
Co-authored-by: jasmussen <joen@git.wordpress.org>

packages/editor/src/components/visual-editor/index.js

@@ -462,7 +462,13 @@ function VisualEditor( {
 								renderingMode !== 'post-only' ||
 									isDesignPostType
 									? 'wp-site-blocks'
-									: `${ blockListLayoutClass } wp-block-post-content` // Ensure root level blocks receive default/flow blockGap styling rules.
+									: `${ blockListLayoutClass } wp-block-post-content`, // Ensure root level blocks receive default/flow blockGap styling rules.
+								{
+									'has-global-padding':
+										renderingMode === 'post-only' &&
+										! isDesignPostType &&
+										hasRootPaddingAwareAlignments,
+								}
 							) }
 							layout={ blockListLayout }
 							dropZoneElement={