The 2020 Tip Challenge has gone viral after several celebrities have left $2,020 in tips. The latest star to participate in the challenge is Tom Selleck, who tipped his food server $2,000, plus $20. Selleck’s $204.68 tab was just a fraction of the tip he left for his server at Elio, an Italian restaurant on the Upper East Side of New York City. Two days before Christmas, “Blue Bloods” co-star Donnie Wahlberg wrote in a tweet, “I found out that my TV Dad #TomSelleck has generously accepted the #2020TipChallenge at Elios Upper East Side! Love ya dad.” The former New Kid on the Block included a photo of Selleck’s receipt, showing the note he wrote to the server: “I am honoring my friend Donnie Wahlberg’s tip challenge with my sincere hope for a better 2020.” In his tweet, Wahlberg also clarified that he didn’t start the challenge but is “proud to be …