Add pre-calculated 0.13.2 block hashes for old blocks

[kkovaacs]

Block commitment signatures on Starknet 0.13.2 will be just a signature over the block hash. To verify pre-0.13.2 blocks we'll need to include a pre-calculated hash of all pre-0.13.2 blocks and use that to verify pre-0.13.2 blocks.

The 0.13.2 state diff commitment will fix the issue where "empty" storage updates showing up in the state diff changed the commitment (and state diff length) so that the commitment calculated by the feeder gateway was different from the value calculated by pathfinder (which ignores empty updates). More info in this thread.