Updated title value in plan factory

What does this MR do?

The introduction of the Premium and Ultimate plans record does not quite reflect the way the Plan factory currently works:

# spec/factories/plans.rb

Plan.all_plans.each do |plan|
      factory :"#{plan}_plan" do
        name { plan }
        title { name.titleize }

as the title for the Ultimate and Premium plans is Ultimate (Formerly Gold) and Premium (Formerly Silver) respectively.

This Plan factory needs to be updated.

Screenshots (strongly suggested)

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