Cross signing fails key match after several times of key mismatch

[bitfriend]

I was testing verification. Once any device is verified, we can try verification for that device no more. Single solution is to logout that device and clear verification history. So I responded key mismatch to avoid logout in every time.

sas.mismatch().await;

I could finish handling of all events prior to SasState::Confirmed via several times of mismatch. I tried key match, but it always failed with CancelCode::KeyMismatch.

sas.confirm().await;