Twenty Twenty-One: Revert usage of `str_contains()` in theme files.

The theme supports WordPress 5.3 or later, while the polyfill for `str_contains()` only exists in WordPress 5.9 or later.

Follow-up to [55988], [57275], [57276].

Props poena.
Fixes #60241.
Built from https://develop.svn.wordpress.org/trunk@57277


git-svn-id: http://core.svn.wordpress.org/trunk@56783 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-content/themes/twentytwentyone/inc/template-functions.php

@@ -445,7 +445,7 @@ function twenty_twenty_one_get_attachment_image_attributes( $attr, $attachment,
 		return $attr;
 	}
 
-	if ( isset( $attr['class'] ) && str_contains( $attr['class'], 'custom-logo' ) ) {
+	if ( isset( $attr['class'] ) && false !== strpos( $attr['class'], 'custom-logo' ) ) {
 		return $attr;
 	}
 

wp-includes/version.php

@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.5-alpha-57276';
+$wp_version = '6.5-alpha-57277';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.