refactor: use native padStart

lib/dialects/postgres/query-generator.js

@@ -794,10 +794,6 @@ class PostgresQueryGenerator extends AbstractQueryGenerator {
     return matches.slice(0, -1);
   }
 
-  padInt(i) {
-    return i < 10 ? `0${i.toString()}` : i.toString();
-  }
-
   dataTypeMapping(tableName, attr, dataType) {
     if (dataType.includes('PRIMARY KEY')) {
       dataType = dataType.replace('PRIMARY KEY', '');

test/integration/model/create.test.js

@@ -913,13 +913,8 @@ describe(Support.getTestDialectTeaser('Model'), () => {
         return userWithDefaults.sync({ force: true }).then(() => {
           return userWithDefaults.create({}).then(user => {
             return userWithDefaults.findByPk(user.id).then(user => {
-              const now = new Date(),
-                pad = function(number) {
-                  if (number > 9) {
-                    return number;
-                  }
-                  return `0${number}`;
-                };
+              const now = new Date();
+              const pad = number =>  number.toString().padStart(2, '0');
 
               expect(user.year).to.equal(`${now.getUTCFullYear()}-${pad(now.getUTCMonth() + 1)}-${pad(now.getUTCDate())}`);
             });