Update gitlab::geo::check rake task: secondary sites must use the same port for SSH as the primary

Problem to solve

Clone URLs for repositories on the Geo secondary sites have a bug of exposing primary node "external_url"

Short term fix for this bug implies that SSH ports for both primary and secondary sites are the same.

Before the long term fix is implemented, to guarantee SSH ports validation, update gitlab:geo:check with the same notice (Secondary sites must use the same port for SSH as the primary.)