Docs: Correct the type for _WP_Dependency::$src property.

The handle source can be set to `false`, which means the item is an alias of other items it depends on.

Follow-up to [7970], [25518], [43661], [47170], [48462], [54470].

Props mehulkaklotar, swissspidy, costdev.
Fixes #57206.

git-svn-id: https://develop.svn.wordpress.org/trunk@54875 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/class-wp-dependency.php

@@ -29,8 +29,10 @@ class _WP_Dependency {
 	/**
 	 * The handle source.
 	 *
+	 * If source is set to false, the item is an alias of other items it depends on.
+	 *
 	 * @since 2.6.0
-	 * @var string
+	 * @var string|false
 	 */
 	public $src;