Add 'dayRate' to the list of pricing field name suffixes
Add 'dayRate' to the list of pricing field name suffixes

If dayRate is not recognised as a pricing field the validation
will raise an exception when trying to get word count from the
pricing pattern.

There's no other easy way to mark pricing fields right now and
renaming dayRate to contain 'price*' doesn't seem appropriate.

Checking the question names in frameworks repo, dayRate doesn't
appear anywhere else at the moment.

alphagov/digitalmarketplace-api,alphagov/digitalmarketplace-api,alphagov/digitalmarketplace-api