Update selects to use custom GitLab styles

app/views/projects/mirrors/_authentication_method.html.haml

@@ -3,10 +3,12 @@
 
 .form-group
   = f.label :auth_method, _('Authentication method'), class: 'label-bold'
-  = f.select :auth_method,
-      options_for_select(auth_options, mirror.auth_method),
-      {}, { class: "form-control js-mirror-auth-type qa-authentication-method" }
-  = f.hidden_field :auth_method, value: "password", class: "js-hidden-mirror-auth-type"
+  .select-wrapper
+    = f.select :auth_method,
+        options_for_select(auth_options, mirror.auth_method),
+        {}, { class: "form-control select-control js-mirror-auth-type qa-authentication-method" }
+    = icon('chevron-down')
+    = f.hidden_field :auth_method, value: "password", class: "js-hidden-mirror-auth-type"
 
 .form-group
   .collapse.js-well-changing-auth

app/views/projects/mirrors/_mirror_repos_form.html.haml

 .form-group
   = label_tag :mirror_direction, _('Mirror direction'), class: 'label-light'
-  = select_tag :mirror_direction, options_for_select([[_('Push'), 'push']]), class: 'form-control js-mirror-direction qa-mirror-direction', disabled: true
+  .select-wrapper
+    = select_tag :mirror_direction, options_for_select([[_('Push'), 'push']]), class: 'form-control select-control js-mirror-direction qa-mirror-direction', disabled: true
+    = icon('chevron-down')
 
 = render partial: "projects/mirrors/mirror_repos_push", locals: { f: f }

changelogs/unreleased/28338-different-dropdown-styles-on-settings-page.yml

+---
+title: Change selects from default browser style to custom style
+merge_request:
+author:
+type: other

ee/app/views/projects/mirrors/_mirror_repos_form.html.haml

@@ -10,7 +10,9 @@
 
 .form-group
   = label_tag :mirror_direction, _('Mirror direction'), class: 'label-light'
-  = select_tag :mirror_direction, options_for_select(direction_options), class: 'form-control js-mirror-direction qa-mirror-direction', disabled: (direction_options.count == 1) || has_existing_pull_mirror
+  .select-wrapper
+    = select_tag :mirror_direction, options_for_select(direction_options), class: 'form-control select-control js-mirror-direction qa-mirror-direction', disabled: (direction_options.count == 1) || has_existing_pull_mirror
+    = icon('chevron-down')
 
 .js-form-insertion-point