Remove redundant lock_unlock.js

[MAILPOET-6319]

packages/js/email-editor/src/private-apis/lock-unlock.js

@@ -1,10 +0,0 @@
-/**
- * WordPress dependencies
- */
-import { __dangerousOptInToUnstableAPIsOnlyForCoreModules } from '@wordpress/private-apis';
-
-export const { lock, unlock } =
-	__dangerousOptInToUnstableAPIsOnlyForCoreModules(
-		'I acknowledge private features are not for use in themes or plugins and doing so will break in the next version of WordPress.',
-		'@wordpress/edit-post' // The module name must be in the list of allowed, so for now I used the package name of the post editor
-	);