Get rid of some warnings from Ruby

spec/support/unit/attribute.rb

@@ -1,7 +1,5 @@
 module UnitTests
   class Attribute
-    attr_reader :name, :column_type, :column_options
-
     DEFAULT_COLUMN_TYPE = :string
     DEFAULT_COLUMN_OPTIONS = {
       null: false,

spec/support/unit/model_creators/active_record.rb

@@ -14,7 +14,6 @@ module UnitTests
         :arguments,
         :attribute_default_values_by_name,
         :attribute_name,
-        :customize_model,
         :model_name,
       )
 

spec/support/unit/validation_matcher_scenario.rb

@@ -4,8 +4,6 @@ module UnitTests
   class ValidationMatcherScenario
     extend Forwardable
 
-    attr_reader :matcher
-
     def initialize(arguments)
       @arguments = arguments.dup
       @matcher_proc = @arguments.delete(:matcher_proc)