Help/About: Update "Support for the Classic Editor plugin will remain in WordPress until 2021" to "through 2021" to further clarify timeline.

Props kjellr.
See #45178.

Built from https://develop.svn.wordpress.org/branches/5.0@43953


git-svn-id: http://core.svn.wordpress.org/branches/5.0@43785 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/about.php

@@ -330,7 +330,7 @@ include( ABSPATH . 'wp-admin/admin-header.php' );
 
 			<div class="feature-section one-col">
 				<div class="col">
-					<p><?php _e( 'Prefer to stick with the familiar Classic Editor? No problem! Support for the Classic Editor plugin will remain in WordPress until 2021.' ); ?></p>
+					<p><?php _e( 'Prefer to stick with the familiar Classic Editor? No problem! Support for the Classic Editor plugin will remain in WordPress through 2021.' ); ?></p>
 					<p><?php _e( 'The Classic Editor plugin restores the previous WordPress editor and the Edit Post screen. It lets you keep using plugins that extend it, add old-style meta boxes, or otherwise depend on the previous editor. To install, visit your plugins page and click the &#8220;Install Now&#8221; button next to &#8220;Classic Editor&#8221;. After the plugin finishes installing, click &#8220;Activate&#8221;. That’s it!' ); ?></p>
 					<p><?php _e( 'Note to users of assistive technology: if you experience usability issues with the block editor, we recommend you continue to use the Classic Editor.' ); ?></p>
 					<?php if ( current_user_can( 'install_plugins' ) ) { ?>

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.0-RC1-43952';
+$wp_version = '5.0-RC1-43953';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.