Claim Assosciated pdf

How about this?

```ruby
def generate_pdf!
  PdfFormBuilder.build(self) { |file| self.pdf = file } 
end
```
  
```ruby
class PdfFormBuilder < Struct.new(:claim)
  class << self
    def build(claim, &block)
      new(claim).tap { |p| p.perform &block }
    end
  end
  
  def perform
    pdf_builder.fill_form(ET1_PDF_PATH, tempfile, document_data, flatten: !Rails.env.test?)
    yield tempfile
    tempfile.close!
  end
end
```