Add missing autoload `Type` (#31123)

Attribute modules (`Attribute`, `Attributes`, `AttributeSet`) uses
`Type`, but referencing `Type` before the modules still fail.

```
% ./bin/test -w test/cases/attribute_test.rb -n test_with_value_from_user_validates_the_value
Run options: -n test_with_value_from_user_validates_the_value --seed 31876

E

Error:
ActiveModel::AttributeTest#test_with_value_from_user_validates_the_value:
NameError: uninitialized constant ActiveModel::AttributeTest::Type
    /Users/kamipo/src/github.com/rails/rails/activemodel/test/cases/attribute_test.rb:233:in `block in <class:AttributeTest>'

bin/test test/cases/attribute_test.rb:232

Finished in 0.002985s, 335.0479 runs/s, 335.0479 assertions/s.
1 runs, 1 assertions, 0 failures, 1 errors, 0 skips
```

Probably we need more autoloading at least `Type`.

17 files changed, 1 insertions, 16 deletions

diff --git a/activemodel/lib/active_model.rb b/activemodel/lib/active_model.rb
index faecd6b96f..a3884206a6 100644
--- a/activemodel/lib/active_model.rb
+++ b/activemodel/lib/active_model.rb
@@ -47,6 +47,7 @@ module ActiveModel
   autoload :SecurePassword
   autoload :Serialization
   autoload :Translation
+  autoload :Type
   autoload :Validations
   autoload :Validator
 
diff --git a/activemodel/lib/active_model/attribute.rb b/activemodel/lib/active_model/attribute.rb
index 0b669db58a..b75ff80b31 100644
--- a/activemodel/lib/active_model/attribute.rb
+++ b/activemodel/lib/active_model/attribute.rb
@@ -1,7 +1,6 @@
 # frozen_string_literal: true
 
 require "active_support/core_ext/object/duplicable"
-require "active_model/type"
 
 module ActiveModel
   class Attribute # :nodoc:
diff --git a/activemodel/lib/active_model/attributes.rb b/activemodel/lib/active_model/attributes.rb
index 6f84748804..cac461b549 100644
--- a/activemodel/lib/active_model/attributes.rb
+++ b/activemodel/lib/active_model/attributes.rb
@@ -1,7 +1,6 @@
 # frozen_string_literal: true
 
 require "active_support/core_ext/object/deep_dup"
-require "active_model/type"
 require "active_model/attribute_set"
 require "active_model/attribute/user_provided_default"
 
diff --git a/activemodel/test/cases/attribute_set_test.rb b/activemodel/test/cases/attribute_set_test.rb
index 50484cb9ce..02c44c5d45 100644
--- a/activemodel/test/cases/attribute_set_test.rb
+++ b/activemodel/test/cases/attribute_set_test.rb
@@ -2,7 +2,6 @@
 
 require "cases/helper"
 require "active_model/attribute_set"
-require "active_model/type"
 
 module ActiveModel
   class AttributeSetTest < ActiveModel::TestCase
diff --git a/activemodel/test/cases/type/big_integer_test.rb b/activemodel/test/cases/type/big_integer_test.rb
index 3d29235d52..0fa0200df4 100644
--- a/activemodel/test/cases/type/big_integer_test.rb
+++ b/activemodel/test/cases/type/big_integer_test.rb
@@ -1,7 +1,6 @@
 # frozen_string_literal: true
 
 require "cases/helper"
-require "active_model/type"
 
 module ActiveModel
   module Type
diff --git a/activemodel/test/cases/type/binary_test.rb b/activemodel/test/cases/type/binary_test.rb
index ef4f125a3b..3221a73e49 100644
--- a/activemodel/test/cases/type/binary_test.rb
+++ b/activemodel/test/cases/type/binary_test.rb
@@ -1,7 +1,6 @@
 # frozen_string_literal: true
 
 require "cases/helper"
-require "active_model/type"
 
 module ActiveModel
   module Type
diff --git a/activemodel/test/cases/type/boolean_test.rb b/activemodel/test/cases/type/boolean_test.rb
index 97b165ab48..2d33579595 100644
--- a/activemodel/test/cases/type/boolean_test.rb
+++ b/activemodel/test/cases/type/boolean_test.rb
@@ -1,7 +1,6 @@
 # frozen_string_literal: true
 
 require "cases/helper"
-require "active_model/type"
 
 module ActiveModel
   module Type
diff --git a/activemodel/test/cases/type/date_test.rb b/activemodel/test/cases/type/date_test.rb
index 15c40a37b7..e8cf178612 100644
--- a/activemodel/test/cases/type/date_test.rb
+++ b/activemodel/test/cases/type/date_test.rb
@@ -1,7 +1,6 @@
 # frozen_string_literal: true
 
 require "cases/helper"
-require "active_model/type"
 
 module ActiveModel
   module Type
diff --git a/activemodel/test/cases/type/date_time_test.rb b/activemodel/test/cases/type/date_time_test.rb
index 598ccf485e..60f62becc2 100644
--- a/activemodel/test/cases/type/date_time_test.rb
+++ b/activemodel/test/cases/type/date_time_test.rb
@@ -1,7 +1,6 @@
 # frozen_string_literal: true
 
 require "cases/helper"
-require "active_model/type"
 
 module ActiveModel
   module Type
diff --git a/activemodel/test/cases/type/decimal_test.rb b/activemodel/test/cases/type/decimal_test.rb
index a0acdc2736..b91d67f95f 100644
--- a/activemodel/test/cases/type/decimal_test.rb
+++ b/activemodel/test/cases/type/decimal_test.rb
@@ -1,7 +1,6 @@
 # frozen_string_literal: true
 
 require "cases/helper"
-require "active_model/type"
 
 module ActiveModel
   module Type
diff --git a/activemodel/test/cases/type/float_test.rb b/activemodel/test/cases/type/float_test.rb
index 46e8b34dfe..28318e06f8 100644
--- a/activemodel/test/cases/type/float_test.rb
+++ b/activemodel/test/cases/type/float_test.rb
@@ -1,7 +1,6 @@
 # frozen_string_literal: true
 
 require "cases/helper"
-require "active_model/type"
 
 module ActiveModel
   module Type
diff --git a/activemodel/test/cases/type/immutable_string_test.rb b/activemodel/test/cases/type/immutable_string_test.rb
index 72f5779dfb..751f753ddb 100644
--- a/activemodel/test/cases/type/immutable_string_test.rb
+++ b/activemodel/test/cases/type/immutable_string_test.rb
@@ -1,7 +1,6 @@
 # frozen_string_literal: true
 
 require "cases/helper"
-require "active_model/type"
 
 module ActiveModel
   module Type
diff --git a/activemodel/test/cases/type/integer_test.rb b/activemodel/test/cases/type/integer_test.rb
index d2e635b447..8c5d18c9b3 100644
--- a/activemodel/test/cases/type/integer_test.rb
+++ b/activemodel/test/cases/type/integer_test.rb
@@ -1,7 +1,6 @@
 # frozen_string_literal: true
 
 require "cases/helper"
-require "active_model/type"
 require "active_support/core_ext/numeric/time"
 
 module ActiveModel
diff --git a/activemodel/test/cases/type/registry_test.rb b/activemodel/test/cases/type/registry_test.rb
index f34104286c..0633ea2538 100644
--- a/activemodel/test/cases/type/registry_test.rb
+++ b/activemodel/test/cases/type/registry_test.rb
@@ -1,7 +1,6 @@
 # frozen_string_literal: true
 
 require "cases/helper"
-require "active_model/type"
 
 module ActiveModel
   module Type
diff --git a/activemodel/test/cases/type/string_test.rb b/activemodel/test/cases/type/string_test.rb
index d39389718b..825c8bb246 100644
--- a/activemodel/test/cases/type/string_test.rb
+++ b/activemodel/test/cases/type/string_test.rb
@@ -1,7 +1,6 @@
 # frozen_string_literal: true
 
 require "cases/helper"
-require "active_model/type"
 
 module ActiveModel
   module Type
diff --git a/activemodel/test/cases/type/time_test.rb b/activemodel/test/cases/type/time_test.rb
index 0bea95768d..f7102d1e97 100644
--- a/activemodel/test/cases/type/time_test.rb
+++ b/activemodel/test/cases/type/time_test.rb
@@ -1,7 +1,6 @@
 # frozen_string_literal: true
 
 require "cases/helper"
-require "active_model/type"
 
 module ActiveModel
   module Type
diff --git a/activemodel/test/cases/type/value_test.rb b/activemodel/test/cases/type/value_test.rb
index 671343b0c8..55b5d9d584 100644
--- a/activemodel/test/cases/type/value_test.rb
+++ b/activemodel/test/cases/type/value_test.rb
@@ -1,7 +1,6 @@
 # frozen_string_literal: true
 
 require "cases/helper"
-require "active_model/type"
 
 module ActiveModel
   module Type