wallet getbids includes bids for previous (expired) auction for same name

Related to: https://github.com/handshake-org/hsd/pull/316

To reproduce:
- start an auction
- place a bid in that auction
- generate blocks to fast-forward past the name expiration
- `getbids`: the bid from the first auction is still present
- start a new auction for the same (expired) name
- `getbids`: the bid from the first auction is still present
- place a new bid, win or lose the auction, etc.
- `getbids`: the bid from the first auction is still present

This is entirely a UI issue (for example, Bob will show the user the old bid on the screen for the new auction, even though this bid IS NOT participating in this new auction). None of the `sendreveal` functions are affected, etc - everything is fine under the hood.

Potential solution: add a parameter to `getbids` like `minconf` or `minheight` to filter out bids that are inactive or for expired auctions.