Make tripleDH manipulate GenericArray<u8, N> over Vec<u8>

upgrade some of the structure contents of the KE types

src/tests/opaque_ke_test.rs

@@ -558,10 +558,7 @@ fn test_complete_flow(
             hex::encode(login_export_key)
         );
     } else {
-        let res = match client_login_result {
-            Err(ProtocolError::VerificationError(PakeError::InvalidLoginError)) => true,
-            _ => false,
-        };
+        let res = matches!(client_login_result, Err(ProtocolError::VerificationError(PakeError::InvalidLoginError)));
         assert!(res);
     }