Replace invalid use of ltrim() in attachment_url_to_postid() with substr().

props bradyvercher.
fixes #30346.
Built from https://develop.svn.wordpress.org/trunk@30501


git-svn-id: http://core.svn.wordpress.org/trunk@30490 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Convert `<title>` to "title tag" in the DocBlock summary for the `admin_title` hook.

Fixes #30437.

Built from https://develop.svn.wordpress.org/trunk@30502


git-svn-id: http://core.svn.wordpress.org/trunk@30491 1a063a9b-81f0-0310-95a4-ce76da25c4cd