`av stack sync` won't update the PR metadata if the commit hashes are aligned

[draftcode]

https://github.com/aviator-co/av/blob/81f6fc4142623c8ac2b71ffbba6ebf549904bd0c/internal/gh/ghui/push.go#L449-L455

In addition to hashes, it should check if the PR metadata matches with the local branch metadata.