Support for Cardano Node 1.26.1

[robinboening]

https://github.com/input-output-hk/cardano-node/releases/tag/1.26.1

In order to support the new release we need to make some changes. This list might not be complete as its from the top of my head after reading the release notes.

• remove the era argument for cardano-cli command otherwise it breaks Automagically determine the era of cli queries IntersectMBO/cardano-node#2470
• cardano-cli query tip JSON response has changed. Scripts need to adapt
  • blockNo is now block
  • slotNo is now slot
  • headerHash is now hash
• build script build.sh needs to define version 1.26.1