replace reconfigure with restart for updating registry_external_url
What does this MR do?
Updates doc https://docs.gitlab.com/ee/administration/pages/index.html by replacing reconfigure with restart in the section https://docs.gitlab.com/ee/administration/pages/index.html#wildcard-domains
Why was this MR needed?
Reconfigure is not enough to update registry_external_url, the value is updated only after restart.