Use has_no_fields(true) in base types to silence warnings

Author: mcelicalderon

lib/graphql_devise/types/mutation_type.rb

@@ -4,6 +4,7 @@ module GraphqlDevise
   module Types
     class MutationType < GraphQL::Schema::Object
       field_class GraphqlDevise::Types::BaseField if Gem::Version.new(GraphQL::VERSION) >= Gem::Version.new('2.0')
+      has_no_fields(true) if respond_to?(:has_no_fields)
     end
   end
 end

lib/graphql_devise/types/query_type.rb

@@ -4,6 +4,7 @@ module GraphqlDevise
   module Types
     class QueryType < GraphQL::Schema::Object
       field_class GraphqlDevise::Types::BaseField if Gem::Version.new(GraphQL::VERSION) >= Gem::Version.new('2.0')
+      has_no_fields(true) if respond_to?(:has_no_fields)
     end
   end
 end