Editor: Remove default "layout" block attribute from WP_Block_Type::get_attributes

The merging behavior which assigns the `layout` attribute in `WP_Block_Type` gets removed.

Props aduth, TimothyBlynJacobs.
Fixes #50257.



git-svn-id: https://develop.svn.wordpress.org/trunk@48118 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/class-wp-block-type.php

@@ -276,18 +276,7 @@ class WP_Block_Type {
 	 */
 	public function get_attributes() {
 		return is_array( $this->attributes ) ?
-			array_merge(
-				$this->attributes,
-				array(
-					'layout' => array(
-						'type' => 'string',
-					),
-				)
-			) :
-			array(
-				'layout' => array(
-					'type' => 'string',
-				),
-			);
+			$this->attributes :
+			array();
 	}
 }