“Peter Rabbit” might not be what Beatrix Potter had in mind when she wrote and illustrated her famous books on which this film is based, but I think she would be OK with its message to children: be good, but when you’re not, be contrite and seek to right your wrong. The titular character, brilliantly voiced by James Corden, hasn’t changed at all since his literary birth. He’s still sneaking into old Mr. McGregor’s (Sam Neill) garden and snatching the yumm...