Taxonomy: Remove `@ignore` annotation on `_get_term_hierarchy()`.

Originally introduced in [32453], the `@ignore` annotation caused the
function to be improperly ignored by the Code Reference parser.

The `@access private` annotation is the correct way to mark a
function for internal use only.

Props coffee2code.
Fixes #45997.
Built from https://develop.svn.wordpress.org/trunk@44755


git-svn-id: http://core.svn.wordpress.org/trunk@44587 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/taxonomy.php

@@ -3439,7 +3439,7 @@ function update_term_cache( $terms, $taxonomy = '' ) {
 /**
  * Retrieves children of taxonomy as Term IDs.
  *
- * @ignore
+ * @access private
  * @since 2.3.0
  *
  * @param string $taxonomy Taxonomy name.

wp-includes/version.php

@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.2-alpha-44749';
+$wp_version = '5.2-alpha-44755';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.