In any case, like any inspection, you can adjust its severity to whatever you find appropriate, including "don't show it at all".
File > Settings > Editor > Inspections > Javascript and Typescript > General > Unresolved reference.
Or directly from the "Show Context Actions" action (Alt+enter or whatever you have it set to, the same combination that shows refactoring actions), you can navigate the inspection like a submenu and select "Edit inspection profile setting".