Game 5 of the 2023 Eastern Conference finals is set for Thursday evening in prime time. The Boston Celtics host the Miami Heat at TD Garden, with the Celtics facing elimination. Boston is trailing 3-1 in the best-of-seven series, including two home losses. The Heat can advance to the 2023 NBA Finals with a victory, though the Celtics responded well in a double-digit Game 4 win on Tuesday. Gabe Vincent (ankle) is listed as questionable to play for Miami. Ti-off is at 8:30 p.m. ET in Boston. Caesars Sportsbook lists Boston as the 8.5-point home favorite, while the over/under, or…