GHSA-M2V9-W374-5HJ9 vyper default functions don't respect nonreentrancy keys

Summary Prior to v0.3.0, default functions did not respect the @nonreentrancy decorator and the lock was not emitted. This is a known bug and was already visible in the issue tracker https://github.com/vyperlang/vyper/issues/2455, but it is being re-issued as an advisory so that tools relying on...