WASHINGTON — A now-canceled $250 million anti-coronavirus ad campaign by the Trump administration was so politically motivated it screened possible celebrity spokespeople based on their support for the president and their liberal ideology, according to documents released Thursday by the House Oversight Committee.The campaign has been shelved while the Department of Health and Human Services reviews allegations of impropriety linked to the effort.But a “PSA Celebrity Tracker” document released by the committee that was updated as recently as Oct. 23 lists some 274 celebrities who were considere…