Fix `CustomCops/AssertNot` to allow it to have failure message

Follow up of #32605.

1 files changed, 2 insertions, 2 deletions

diff --git a/actionview/test/template/partial_iteration_test.rb b/actionview/test/template/partial_iteration_test.rb
index 06bbdabac0..1c3c566667 100644
--- a/actionview/test/template/partial_iteration_test.rb
+++ b/actionview/test/template/partial_iteration_test.rb
@@ -18,7 +18,7 @@ class PartialIterationTest < ActiveSupport::TestCase
   def test_first_is_false_unless_current_is_at_the_first_index
     iteration = ActionView::PartialIteration.new 3
     iteration.iterate!
-    assert !iteration.first?, "not first when current is 1"
+    assert_not iteration.first?, "not first when current is 1"
   end
 
   def test_last_is_true_when_current_is_at_the_last_index
@@ -30,6 +30,6 @@ class PartialIterationTest < ActiveSupport::TestCase
 
   def test_last_is_false_unless_current_is_at_the_last_index
     iteration = ActionView::PartialIteration.new 3
-    assert !iteration.last?, "not last when current is 0"
+    assert_not iteration.last?, "not last when current is 0"
   end
 end