Fixed the return type of method profile of class Logger

[Mallikarjun-0]

There is a possibility that the method profile of class Logger might return a boolean.

[Mallikarjun-0]

Hi @DABH, I think this PR got skipped because of its brevity.

Summary

This PR, fixes the return type hint of the method profile() of class Logger defined in logger.js. The current type hint for this method only has this impling Logger but profile() can also return boolean

Example:

const winston = require('winston');

const logger = winston.createLogger({
  level: 'info',
  format: winston.format.simple(),
  transports: [
    new winston.transports.Console()
  ]
});

var temp = logger.profile('test');
console.log(typeof temp);           // prints 'object' as 'Logger' is returned

setTimeout(() => {
  temp = logger.profile('test');
  console.log(typeof temp);         // prints 'boolean`
}, 1000);