AST has removed the overhang of its outstanding warrants -- and collected a big bundle of cash to boot.After sliding lower all week long, shares of AST SpaceMobile (ASTS 8.05%) turned around and moved higher on Friday, gaining 5% through 10:45 a.m. ET. Why? Probably because of AST's 8-k filing with the SEC yesterday.More limited in focus than a 10-K filing, an 8-K highlights news important to a company. In this case, AST wanted to emphasize what it said in a press release issued Wednesday: It has officially ...