Docs: Add an explanation for the dynamic portion of the `{$taxonomy}_term_edit_form_top` hook, introduced in [36526].

See #32246.


git-svn-id: https://develop.svn.wordpress.org/trunk@36577 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/edit-tag-form.php

@@ -107,6 +107,8 @@ wp_nonce_field( 'update-tag_' . $term_id );
  *
  * At this point, the required hidden fields and nonces have already been output.
  *
+ * The dynamic portion of the hook name, `$taxonomy`, refers to the taxonomy slug.
+ *
  * @since 4.5.0
  *
  * @param object $tag      Current taxonomy term object.