GHSA-rrqf-w74j-24ff: Indico has a Cross-Site-Scripting during account creation

There is a Cross-Site-Scripting vulnerability during account creation when redirecting after the account has been successfully created. Exploitation requires the user to initiate the account creation process with a maliciously crafted link, and then finalize the signup process. Because of this, it can only target newly created (and thus unprivileged) Indico users so the benefits of exploiting it are very limited.