DEV: Remove experimental setting row for chat threads (#22730)

plugins/chat/db/migrate/20230721025249_remove_experimental_site_setting_for_threads.rb

@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+class RemoveExperimentalSiteSettingForThreads < ActiveRecord::Migration[7.0]
+  def up
+    execute "DELETE FROM site_settings WHERE name='enable_experimental_chat_threaded_discussions'"
+  end
+
+  def down
+    raise ActiveRecord::IrreversibleMigration
+  end
+end