Fix overlong line with horrible formatting

lib/mutant/mutator/node/send.rb

@@ -180,7 +180,10 @@ module Mutant
         # @api private
         #
         def emit_implicit_self
-          if receiver.type == :self && !KEYWORDS.include?(selector) && !attribute_assignment? && !OP_ASSIGN.include?(parent_type)
+          if receiver.type == :self &&
+             !KEYWORDS.include?(selector) &&
+             !attribute_assignment? &&
+             !OP_ASSIGN.include?(parent_type)
             emit_receiver(nil)
           end
         end

lib/mutant/mutator/node/send/attribute_assignment.rb

@@ -49,4 +49,3 @@ module Mutant
     end # Node
   end # Mutator
 end # Mutant
-