Use correct load method

Author: arahlin

serve/src/spt3g-json-serve-files.cxx

@@ -260,7 +260,7 @@ static void handle_g3(const httplib::Request & req, httplib::Response & resp)
 					if (!first)
 						os << ","  << std::endl;
 
-					frame.load(ifs);
+					frame.loads(ifs);
 					if (i++ >= n_skip) {
 						frame.saveJSON(os);
 						first = false;