The federal government is converting another convention center into a shelter for illegal immigrants amid a border surge that has shown no sign of slowing down. Health Secretary Xavier Becerra requested help from the city of San Diego to house some of the unaccompanied minors who have been crossing into the United States from Mexico, Mayor Todd Gloria and San Diego County Board of Supervisors Chair Nathan Fletcher, both Democrats, said in a joint statement. The officials agreed over the weekend to open the San Diego Convention Center to the federal government for use as a temporary shelter. “The city and county will support this federally funded effort by providing vital services to these vulnerable children who came to our country seeking safety,” Gloria and Fletcher said. “We are working closely with our federal partners to finalize the details for preparing to receive these young people and provide them with …