It’s fitting: the last song recorded by Toby Keith before his passing February 5 was a collaboration with Hardy, Luke Combs and the late Joe Diffie on the reflective, bittersweet Diffie classic “Ships That Don’t Come In.” The song was recorded shortly before Toby’s final three shows in Las Vegas in mid-December and is included on the Diffie tribute album “Hixtape Vol 3: Difftape,” which was released Friday.