Changed
- Relax httpx dependency [(408)](https://github.com/michaelhly/solana-py/pull/408)
- Remove experimental and flawed BlockhashCache [(408)](https://github.com/michaelhly/solana-py/pull/408). This was a footgun because it broke a lot.
- Upgrade to Solders 0.21.0 (fixes aarch64 compatibility issues) [(402)](https://github.com/michaelhly/solana-py/pull/402)