The triple bill of one-acts at the Irish Repertory Theatre is a rare chance to see plays by Lady Gregory, William Butler Yeats and John Millington Synge, although in small-space productions downstairs at the invaluable venue. One may not feel that the first two plays, The Pot of Broth and The Rising of the Moon, should occupy the umbrella title of Three Small Irish Masterpieces alongside Synge’s Riders to the Sea, which fits the bill; the first two seem slight by comparison. But they make a pleasant enough evening of unfamiliar entertainment, enhanced by the proximity to St. Patrick’s Day.