[BUG] Governance contract, Query bug

[kaisbaccour]

Hey guys, I Found this issue while copying your code to terra-vegas casino
This issue is a confusing query issue in the governance contract.
The confusion happens in this line
https://github.com/Anchor-Protocol/anchor-token-contracts/blob/main/contracts/gov/src/contract.rs#L598

This happens when the voting period is finished but no tx has happened yet to update the state.
This could be mitigated by adding a new condition on the query function to make sure we send the right response.
I opened a PR here #31
I put the Status to Expired because I did not want to add a new PollStatus::WaitingOnTransactionToEndPoll. But I believer a new status should be there to better describe the Poll status (Waiting On Transaction To End Poll)

Please check the Pull request