Use JceTlsMLKemDomain instead of KemUtil directly

Author: peterdettman

tls/src/main/java/org/bouncycastle/tls/crypto/impl/jcajce/JceTlsMLKem.java

@@ -35,7 +35,7 @@ public byte[] generateEphemeral() throws IOException
         {
             KeyPair kp = domain.generateKeyPair();
             this.privateKey = kp.getPrivate();
-            return KemUtil.encodePublicKey(kp.getPublic());
+            return domain.encodePublicKey(kp.getPublic());
         }
     }