Fix typo s/Topic/Tag/

`Topic` isn't loaded in this test file.

1 files changed, 1 insertions, 1 deletions

diff --git a/activerecord/test/cases/transaction_isolation_test.rb b/activerecord/test/cases/transaction_isolation_test.rb
index 8bcf121f15..9663955f1f 100644
--- a/activerecord/test/cases/transaction_isolation_test.rb
+++ b/activerecord/test/cases/transaction_isolation_test.rb
@@ -11,7 +11,7 @@ unless ActiveRecord::Base.connection.supports_transaction_isolation?
 
     test "setting the isolation level raises an error" do
       assert_raises(ActiveRecord::TransactionIsolationError) do
-        Tag.transaction(isolation: :serializable) { Topic.connection.materialize_transactions }
+        Tag.transaction(isolation: :serializable) { Tag.connection.materialize_transactions }
       end
     end
   end