If you want to control severity at LoggingWinston.

https://stackoverflow.com/questions/58055551/structured-logs-in-google-cloud-run-not-being-parsed-using-winston-for-logging

  
const winston = require('winston');  
const useFormat = winston.format.combine(  
  winston.format((info, opts) => {  
    let level = info.level.toUpperCase();  
      if(level === 'VERBOSE') {  
        level = 'DEBUG';  
      }  
  
      info['severity'] = level;  
      delete info.level;  
      return info;  
  })(),  
  winston.format.json());  
const { LoggingWinston } = require('@google-cloud/logging-winston');  
const loggingWinston = new LoggingWinston();  
const logger = winston.createLogger({  
  level: 'debug',  
  format: useFormat,  
  transports: [  
    new winston.transports.Console(),  
    loggingWinston  
  ]  
});