title: Got error after migration from rspec-rails 2.x to 3.x
body: <p>Before migration these steps passed, but now I get errors:</p>
  
  <pre><code>Failures:
  
    1) RegistrationPayment .opts
       Failure/Error: allow(Rails.configuration).to receive(:pim_product_url).and_return(product_url)
       ArgumentError:
         wrong number of arguments (2 for 1)
       # ./spec/lib/registration_payment_spec.rb:47:in `block (2 levels) in &lt;top (required)&gt;'
  
    2) RegistrationPayment .new
       Failure/Error: allow(Rails.configuration).to receive(:pim_product_offerings).and_return([offering_id])
       ArgumentError:
         wrong number of arguments (2 for 1)
       # ./spec/lib/registration_payment_spec.rb:38:in `block (2 levels) in &lt;top (required)&gt;'
  </code></pre>
  
  <p>I define <code>product_url</code> and <code>offering_id</code> such way </p>
  
  <pre><code>  let(:product_url) { '/product/url' }
    let(:offering_id) { '3000319' }
  </code></pre>