PHOENIX — The Pistons have been without Isaiah Stewart for the last seven games — eight after Wednesday’s game against the Phoenix Suns — due to an injury, but his return to the lineup could be in jeopardy. Stewart reportedly punched Suns center Drew Eubanks in the back tunnels of Footprint Center in Wednesday’s game in Phoenix, according to The Athletic’s Shams Charania. Stewart has been sidelined due to a left ankle injury and a team spokesperson told reporters on Monday that he began his ramp-up process and was expected to return to the lineup after the All-Star break. The NBA is expected t…