chore: Enable help center for self-hosted accounts (#5458)

db/migrate/20220920014549_enable_help_center.rb

@@ -0,0 +1,12 @@
+class EnableHelpCenter < ActiveRecord::Migration[6.1]
+  def change
+    return if ENV['DEPLOYMENT_ENV'] == 'cloud'
+
+    Account.find_in_batches do |account_batch|
+      account_batch.each do |account|
+        account.enable_features('help_center')
+        account.save!
+      end
+    end
+  end
+end