Added
- Add `bankrun_fixture` to `anchorpy.pytest_plugin`. This calls
[`solders.bankrun.start()`](https://kevinheavey.github.io/solders/examples/bankrun.html)
and deploys programs to the test environment.
Changed
- Use latest solders and solana-py.
- Don't do any signing or blockhash fetching in `Provider.send`, `.send_all` and `.simulate`.
- Remove `SendTxRequest` class
- Replace `Transaction` with `VersionedTransaction` in the `.transaction` namespace.
- Add mandatory `payer` and `blockhash` params to `.transaction` so it always returns a fully-formed tx.