Update `since` annotation on `allow_empty_comment` hook.

Originally introduced in [42661].

Fixes #16979.
Built from https://develop.svn.wordpress.org/trunk@44364


git-svn-id: http://core.svn.wordpress.org/trunk@44194 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/comment.php

@@ -3246,7 +3246,7 @@ function wp_handle_comment_submission( $comment_data ) {
 	/**
 	 * Filters whether an empty comment should be allowed.
 	 *
-	 * @since 5.0.0
+	 * @since 5.1.0
 	 *
 	 * @param bool  $allow_empty_comment Whether to allow empty comments. Default false.
 	 * @param array $commentdata         Array of comment data to be sent to wp_insert_comment().

wp-includes/version.php

@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.1-alpha-44363';
+$wp_version = '5.1-alpha-44364';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.