feat(securejoin): do not create 1:1 chat on Alice's side until vc-request-with-auth

vc-request is an unencrypted message
that Bob sends when he does not have Alice's key.
It also does not contain
Bob's avatar and name,
so the contact has only the email address
at this point and it is too early
to show it.

src/securejoin/securejoin_tests.rs

@@ -129,7 +129,7 @@ async fn test_setup_contact_ex(case: SetupContactCase) {
             .await
             .unwrap()
             .len(),
-        1
+        0
     );
 
     let sent = alice.pop_sent_msg().await;