x448 test vectors (#4576)

diff --git a/docs/development/test-vectors.rst b/docs/development/test-vectors.rst
index e5ff70b..a3ffc9a 100644
--- a/docs/development/test-vectors.rst
+++ b/docs/development/test-vectors.rst
@@ -48,7 +48,7 @@
   * `Botan's ECC private keys`_.
 * `asymmetric/public/PKCS1/dsa.pub.pem`_ is a PKCS1 DSA public key from the
   Ruby test suite.
-* X25519 test vectors from :rfc:`7748`.
+* X25519 and X448 test vectors from :rfc:`7748`.
 * RSA OAEP with custom label from the `BoringSSL evp tests`_.