authenticode: Ignore expected warnings in error tests

Author: nicholasbishop

authenticode/tests/test_errors.rs

@@ -6,6 +6,9 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+// Ignore warnings from not using the return value of `format!`.
+#![expect(unused_must_use)]
+
 use authenticode::{
     AttributeCertificateAuthenticodeError, AttributeCertificateError,
     AuthenticodeSignatureParseError, PeOffsetError,