Rename the action to editor.__unstableSavePost

Author: jsnajdr

packages/edit-post/src/store/actions.js

@@ -566,7 +566,7 @@ export const initializeMetaBoxes =
 
 		// Save metaboxes on save completion, except for autosaves.
 		addFilter(
-			'editor.SavePost',
+			'editor.__unstableSavePost',
 			'core/edit-post/save-metaboxes',
 			( previous, options ) =>
 				previous.then( () => {

packages/editor/src/store/actions.js

@@ -189,7 +189,7 @@ export const savePost =
 
 		if ( ! error ) {
 			await applyFilters(
-				'editor.SavePost',
+				'editor.__unstableSavePost',
 				Promise.resolve(),
 				options
 			).catch( ( err ) => {