test(olm): Add mutation tests for pre_key

Relates to: #78

Signed-off-by: Johannes Marbach <[email protected]>

src/olm/account/mod.rs

@@ -780,6 +780,7 @@ mod test {
 
  if let OlmMessage::PreKey(m) = olm_message {
  assert_eq!(m.session_keys(), alice_session.session_keys());
+ assert_eq!(m.session_id(), alice_session.session_id());
 
  let InboundCreationResult { session: mut bob_session, plaintext } =
  bob.create_inbound_session(alice.curve25519_key(), &m)?;