delete X-UA-Compatible (#6068)

* delete X-UA-Compatible

* undo

* restore

app/views/layouts/application.html.haml

@@ -2,8 +2,7 @@
 %html{ lang: I18n.locale }
   %head
     %meta{ charset: 'utf-8' }/
-    %meta{ name: 'viewport', content: 'width=device-width, initial-scale=1' }/
-    %meta{ 'http-equiv' => 'X-UA-Compatible', content: 'IE=edge' }/
+    %meta{ name: 'viewport', content: 'width=device-width, initial-scale=1' }/   
     %link{ rel: 'icon', href: favicon_path, type: 'image/x-icon' }/
     %link{ rel: 'apple-touch-icon', sizes: '180x180', href: '/apple-touch-icon.png' }/
     %link{ rel: 'mask-icon', href: '/mask-icon.svg', color: '#2B90D9' }/