Connecticut’s AFL-CIO voted behind closed doors to endorse Gov. Ned Lamont for reelection to a third term Friday, a day after interviewing the governor and Josh Elliott, his challenger for the Democratic nomination. The two-thirds vote necessary for an endorsement did not come quickly, reflecting resentment over prolonged state contract talks, Lamont’s veto of a bill that would have provided jobless benefits for strikers and his opposition to ra…