Build: Update webpack to v5.x

Update webpack version to latest version https://www.npmjs.com/package/webpack. This aligns closer with how the Gutenberg plugin handles WordPress packages. Related update in Gutenberg from August 2021: https://github.com/WordPress/gutenberg/pull/33818.

Props walbo, desrosj, mukesh27.
Fixes #51750.




git-svn-id: https://develop.svn.wordpress.org/trunk@53135 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/blocks/file/view.asset.php

@@ -1 +1 @@
-<?php return array('dependencies' => array(), 'version' => '499eaf2efb98327a07f222e92d742380');
+<?php return array('dependencies' => array(), 'version' => '9a1dbe2fc8e62a7e82dd0d30439951b3');

src/wp-includes/blocks/file/view.min.asset.php

@@ -1 +1 @@
-<?php return array('dependencies' => array(), 'version' => 'e8d668b8e69d9bf1c99dc250d92f2b72');
+<?php return array('dependencies' => array(), 'version' => 'c7ee2db603af4ed37bd6b1d2bb4a51bf');