What was the victory song that peeves sang in seventh Harry Potter book?

You're probably thinking of "The Song of the Goblins" which was sung by the goblins in the seventh book, not Peeves. It wasn't a victory song but rather a rousing and rather disturbing tune they sang as they raided Gringotts Wizarding Bank.

Peeves, the poltergeist, didn't have any particular victory song, but he was known for singing and making noise whenever he felt like it.

Let me know if you have any other questions about the Harry Potter series!