Allow the 60 sec timeout value for displaying replication lag icon to be configurable
The Geo node sync information box will show an icon next to each item indicating there's replication lag (https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/5653). The current value used to determine whether or not to show the icon is 60 seconds which is a reasonable default, but for large installations (e.g. gitlab.com) this may need to be set higher potentially.