By Brenda Goh SHANGHAI (Reuters) – Four people at a renowned Shanghai hospital were wounded by a knife-wielding assailant on Saturday, in the second reported stabbing incident after a COVID-19 lockdown of the financial hub was lifted early in June. Officers raced to the more than 100-year-old Ruijin Hospital on Saturday morning after receiving calls about an attack, police said. Videos on social media showed chaos as visitors clambered under turnstiles to get out of the hospital while doctors were seen running out with their patients, some in wheelchairs and one on a mobile bed. A long trail o…