1. Update of pallet contracts that makes it compatible with Ink! 4.0.beta
2. Adjustments of the validator network:
   1. The legacy back-up network is removed, as it is not necessary anymore.
   2. The nodes establish now only one connection instead of two.
3. Update of AlephBFT to version 0.20, which introduces more efficient unit requests and various other improvements.
4. Validator suspension now has an additional effect of “chilling” the validator.