Apply gl-button class to buttons

ee/app/views/admin/application_settings/_custom_templates_form.html.haml

@@ -3,7 +3,7 @@
     .settings-header
       %h4
         = _('Custom project templates')
-      %button.btn.js-settings-toggle{ type: 'button' }
+      %button.btn.gl-button.js-settings-toggle{ type: 'button' }
         = expanded ? _('Collapse') : _('Expand')
       %p
         = _('Select the custom project template source group.')

ee/app/views/admin/application_settings/_templates.html.haml

@@ -3,7 +3,7 @@
     .settings-header
       %h4
         = _('Templates')
-      %button.btn.js-settings-toggle{ type: 'button' }
+      %button.btn.gl-button.js-settings-toggle{ type: 'button' }
         = expanded ? _('Collapse') : _('Expand')
       %p
         = _('Set instance-wide template repository')