Add preemptive redirect rules for Ofsted inspection reports

Ofsted has c. 170,000 report pages for various schools and institutions, each with pdfs and other attachments. These will eventually be redeveloped into some sort of a service domain, but are currently excluded from transition as a tool/transaction. These will temporarily be hosted at a subdomain: http://reports.ofsted.gov.uk

This rule prevents the need for the transition tool to contain these 400,000(?) mappings; the site structure is consistent across both namespaces.
The tests are failing. This line should be:
```ruby
redirect("http://reports.ofsted.gov.uk/provider/files/#{$1}/urn/#{$2}")
```