Only use update to create/change tracing settings

ee/app/controllers/projects/settings/operations_controller.rb

@@ -15,13 +15,6 @@ module Projects
         render_result(result)
       end
 
-      def create
-        result = EE::TracingSettingService.new(project, current_user, operations_params).execute
-        @tracing_setting = project.tracing_setting
-
-        render_result(result)
-      end
-
       private
 
       helper_method :tracing_setting

ee/app/views/projects/settings/operations/show.html.haml

@@ -19,7 +19,7 @@
         %span
           = _('Tracing')
     = _("To open Jaeger and easily view tracing from GitLab, link the %{link} page to your server").html_safe % { link: tracing_link }
-  = form_for setting, as: :tracing_settings, url: project_settings_operations_path(@project) do |f|
+  = form_for setting, as: :tracing_settings, url: project_settings_operations_path(@project), method: :patch do |f|
     = form_errors(setting)
     .form-group
       = f.label :external_url, _('Jaeger URL'), class: 'label-bold'