Ex-White House doctor, Ronny Jackson (R-Tx.), is demanding that President Joe Biden take a cognitive test or drop out of his the 2024 race presidential race altogether. The US lawmaker who has repeatedly questioned whether the 80-year-old president has the cognitive ability to be commander-in-chief, renewed calls for a mental evaluation as Biden announced on Tuesday, April 24, that he was seeking re-election. Jackson made the demands in a letter, obtained by The Post, which is currently …