Use Botan 3.1.1 for tests

The all-zero Ed25519 public key is rejected by botan_pubkey_check_key()
when the key is loaded.

Note that Botan 3 requires GCC 11 or CLANG 14, i.e. can't easily be built
on Debian bullseye or Ubuntu 20.04.

The thread-local storage function gets flagged via various botan FFI
functions when using Botan 3, whitelist that instead of all of them.

src/libstrongswan/tests/suites/test_ed25519.c

@@ -559,10 +559,12 @@ START_TEST(test_ed25519_fail)
 	pubkey->destroy(pubkey);
 	pubkey = lib->creds->create(lib->creds, CRED_PUBLIC_KEY, KEY_ED25519,
 					BUILD_BLOB_ASN1_DER, zero_pk, BUILD_END);
-	ck_assert(pubkey != NULL);
-	ck_assert(!pubkey->verify(pubkey, SIGN_ED25519, NULL, sig_tests[0].msg,
-							  sig));
-	pubkey->destroy(pubkey);
+	if (pubkey)
+	{
+		ck_assert(!pubkey->verify(pubkey, SIGN_ED25519, NULL, sig_tests[0].msg,
+								  sig));
+		pubkey->destroy(pubkey);
+	}
 }
 END_TEST