Fix missing validation_error: Response#validate_structure was raising Exception instead of ValidationError

Author: patriciomacadden

lib/onelogin/ruby-saml/response.rb

@@ -126,7 +126,7 @@ def validate_structure(soft = true)
         if soft
           @schema.validate(@xml).map{ return false }
         else
-          @schema.validate(@xml).map{ |error| raise(Exception.new("#{error.message}\n\n#{@xml.to_s}")) }
+          @schema.validate(@xml).map{ |error| validation_error("#{error.message}\n\n#{@xml.to_s}") }
         end
       end