Reset only migration models

What does this MR do?

Reset only migration models

Why was this MR needed?

So that we could make sure migration tests could run even if geo is not setup in EE.

This is because we have a model like this:

class Geo::BaseRegistry < ActiveRecord::Base
  def self.connection
    raise 'Geo secondary database is not configured' unless Gitlab::Geo.geo_database_configured?

    super
  end
end

What are the relevant issue numbers?

Closes #36052 (closed)