chore: remove deprecated `User.emailConfirm` [breaking]

Use `User.email.confirmByCode` instead.

src/user/email.js

@@ -2,7 +2,6 @@
 'use strict';
 
 const nconf = require('nconf');
-const winston = require('winston');
 
 const user = require('./index');
 const utils = require('../utils');
@@ -88,12 +87,6 @@ UserEmail.sendValidationEmail = async function (uid, options) {
 	return confirm_code;
 };
 
-UserEmail.confirm = async function (code) {
-	// TODO: remove in 1.17.0
-	winston.warn('[deprecated] User.email.confirm deprecated use User.email.confirmByCode');
-	await UserEmail.confirmByCode(code);
-};
-
 // confirm email by code sent by confirmation email
 UserEmail.confirmByCode = async function (code) {
 	const confirmObj = await db.getObject('confirm:' + code);