When admin finally updates the server version to v1.2.1 it will have the account deletion option available.
You only have an account at the forums though. You may have BOINC installed, but you don't have this project added, so your computer isn't being used. In that case you can uninstall BOINC. And if you didn't even have that installed, absolutely nothing to worry about, you then only have an account here that you don't have to do anything with.