unit-tests: Allow Ed448 implementations to fail parsing small-order public keys

We already adapted the Ed25519 test with 36b1a6d76c ("Use Botan 3.1.1
for tests"), now wolfSSL refuses to create such Ed448 keys as well.

src/libstrongswan/tests/suites/test_ed448.c

@@ -621,10 +621,12 @@ START_TEST(test_ed448_fail)
 	pubkey->destroy(pubkey);
 	pubkey = lib->creds->create(lib->creds, CRED_PUBLIC_KEY, KEY_ED448,
 					BUILD_BLOB_ASN1_DER, zero_pk, BUILD_END);
-	ck_assert(pubkey != NULL);
-	ck_assert(!pubkey->verify(pubkey, SIGN_ED448, NULL, sig_tests[0].msg,
-							  sig));
-	pubkey->destroy(pubkey);
+	if (pubkey)
+	{
+		ck_assert(!pubkey->verify(pubkey, SIGN_ED448, NULL, sig_tests[0].msg,
+								  sig));
+		pubkey->destroy(pubkey);
+	}
 }
 END_TEST