Editor: Update WordPress packages to make editor full-screen by default.

The following package versions were changed:
@wordpress/e2e-test-utils: 4.3.0 -> 4.3.1
@wordpress/edit-post: 3.13.3 -> 3.13.4
This commit update allows the following PR to be part of trunk https://github.com/WordPress/gutenberg/pull/20611.

Props youknowriad, mcsf, mapk.
Fixes: #49574.
Built from https://develop.svn.wordpress.org/trunk@47421


git-svn-id: http://core.svn.wordpress.org/trunk@47208 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/js/dist/edit-post.js

@@ -1395,7 +1395,8 @@ var PREFERENCES_DEFAULTS = {
   features: {
     fixedToolbar: false,
     showInserterHelpPanel: true,
-    welcomeGuide: true
+    welcomeGuide: true,
+    fullscreenMode: true
   },
   pinnedPluginItems: {},
   hiddenBlockTypes: [],

wp-includes/version.php

@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.4-beta3-47420';
+$wp_version = '5.4-beta3-47421';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.