Values for mainnet and testnet will be specified in a follow-up PR that can be
scrutinized accordingly. This structure is required for use in snapshot activation
logic.
This is a backport of core#19806 [4/8]
https://github.com/bitcoin/bitcoin/pull/19806/commits/7a6c46b37edb8bfa0085d202aa7e9427d5e4fceb
Note that the hash values for the regtest network must be adjusted to work with Bitcoin ABC. The correctness of these two hashes will be tested when `chainstatemanager_activate_snapshot` is implemented in a next commit. The new test introduced in this diff only tests that these hardcoded hashes will not be accidentaly or maliciously modified.