clean code

src/migrations/20180926134048-make-email-unique.js

@@ -1,4 +1,3 @@
-require('module-alias/register');
 const logger = require('@alias/logger')('growi:migrate:make-email-unique');
 
 const mongoose = require('mongoose');

src/migrations/20180927102719-init-serverurl.js

@@ -1,6 +1,5 @@
 
 
-require('module-alias/register');
 const logger = require('@alias/logger')('growi:migrate:init-serverurl');
 
 const mongoose = require('mongoose');

src/migrations/20181019114028-abolish-page-group-relation.js

@@ -1,4 +1,3 @@
-require('module-alias/register');
 const logger = require('@alias/logger')('growi:migrate:abolish-page-group-relation');
 
 const mongoose = require('mongoose');

src/migrations/20190618055300-abolish-crowi-classic-auth.js

@@ -1,4 +1,3 @@
-require('module-alias/register');
 const logger = require('@alias/logger')('growi:migrate:make-email-unique');
 
 const mongoose = require('mongoose');

src/migrations/20190618104011-add-config-app-installed.js

@@ -1,4 +1,3 @@
-require('module-alias/register');
 const logger = require('@alias/logger')('growi:migrate:add-config-app-installed');
 
 const mongoose = require('mongoose');