Update a few other instances that were using refute methods

Prefer assert_not* in general.

test/controllers/helper_methods_test.rb

@@ -14,8 +14,8 @@ class HelperMethodsTest < Devise::ControllerTestCase
   end
 
   test 'does not respond_to helper or helper_method' do
-    refute_respond_to @controller.class, :helper
-    refute_respond_to @controller.class, :helper_method
+    assert_not_respond_to @controller.class, :helper
+    assert_not_respond_to @controller.class, :helper_method
   end
 
   test 'defines methods like current_user' do

test/models/confirmable_test.rb

@@ -28,7 +28,7 @@ class ConfirmableTest < ActiveSupport::TestCase
     confirmation_tokens = []
     3.times do
       token = create_user.confirmation_token
-      refute_includes confirmation_tokens, token
+      assert_not_includes confirmation_tokens, token
       confirmation_tokens << token
     end
   end

test/models/lockable_test.rb

@@ -72,8 +72,8 @@ class LockableTest < ActiveSupport::TestCase
   test "reset_failed_attempts! does not try to reset if not using failed attempts strategy" do
     admin = create_admin
 
-    refute_respond_to admin, :failed_attempts
-    refute admin.reset_failed_attempts!
+    assert_not_respond_to admin, :failed_attempts
+    assert_not admin.reset_failed_attempts!
   end
 
   test 'should be valid for authentication with a unlocked user' do
@@ -147,7 +147,7 @@ class LockableTest < ActiveSupport::TestCase
       user = create_user
       user.lock_access!
       token = user.unlock_token
-      refute_includes unlock_tokens, token
+      assert_not_includes unlock_tokens, token
       unlock_tokens << token
     end
   end

test/models/recoverable_test.rb

@@ -18,7 +18,7 @@ class RecoverableTest < ActiveSupport::TestCase
       user = create_user
       user.send_reset_password_instructions
       token = user.reset_password_token
-      refute_includes reset_password_tokens, token
+      assert_not_includes reset_password_tokens, token
       reset_password_tokens << token
     end
   end