NEEDHAM — There will be others, and if coach Jeff Moore stays at Tabor Academy for any significant time, there may be plenty of others. But on Saturday, the Seawolves notched the first, true, signature win of Moore’s tenure at Tabor, when they defeated St. Sebastian’s, 38-28. Although the week before Tabor beat a very good Rivers team, this victory over St. Sebastian’s stands out. With the victory, Tabor improves…