release: bump version to 0.28.1

release: bump version to 0.28.1

Summary

This patch release backports (from the BDK 1.0 dev branch) a fix for a bug in the policy condition calculation and adds a new taproot single key descriptor template (BIP-86). The policy condition calculation bug can cause issues when a policy subtree fails due to missing info even if it's not selected when creating a new transaction, errors on unused policy paths are now ignored.

Fixed

- Backported #932 fix for policy condition calculation #1008

Added

-  Backported #840 taproot descriptor template (BIP-86) #1033