A social media influencer is on the cusp of completing his charitable 30-day challenge of turning a vacant retail unit into a thriving café with only £300. TikTok star Max McCann has invited the people of Newbury to join him to celebrate the completion of the challenge and take part in a display of collective generosity this weekend. The café — called McCann’s Coffee Shop and located in the Kennet Centre — was set up with giving back to the community in mind, with Mr McCann encouraging customers to pay forward for coffees that would be donated to those in need. He said: “Since the launch of ou…